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Moleaer™ Launches nanoBoost™, the Most Efficient Oxygen Delivery Mechanism for Commercial Greenhouses

Moleaer announces commercial partnership with Hort Americas

LOS ANGELES

Moleaer Inc., the leading manufacturer of industrial scale nanobubble generators, expands its innovative product line with the new nanoBoost Nanobubble Generator, ideally suited for applications such as hydroponics, pond management, and irrigation.

Moleaer Inc., the leading manufacturer of industrial scale nanobubble generators, expands its innovative product line with the new nanoBoost Nanobubble Generator, ideally suited for applications such as hydroponics, pond management, and irrigation (PRNewsfoto/H2C Group)

Like the existing Moleaer industrial XTB Nanobubble Generator, the compact nanoBoost is a cost-effective and simple-to-install solution to deliver a supplementary source of oxygen-enriched nanobubbles that remain in suspension longer than conventional micro bubbles, efficiently oxygenating the entire body of water and providing a reserve of oxygen encapsulated within the bubbles.

One of the prime beneficiaries of the nanoBoost are commercial greenhouses.  Moleaer’s nanoBoost has been proven to significantly increase plant growth, improve size uniformity, reduce stress and prevent root disease under the most extreme conditions. It delivers billions of nanobubbles with 200-times the inter-facial surface area when compared to micro bubbles, making them far superior in transporting valuable oxygen to a plant’s root system. In addition, the surface of the nanobubbles is negatively charged, attracting nutrient salts and enhancing nutrient uptake. Nanobubbles also increase the mobility of water molecules, potentially improving plant transpiration.

“We installed the 50-GPM nanoBoost in our Dallas-based hydroponics demonstration greenhouse in order to improve production of leafy greens and culinary herbs during the most difficult production season.  Our thought was that if we enhance and maintained higher dissolved oxygen levels, we should be able to improve crop health and ultimately improve yield,” said Chris Higgins, General Manager of Hort Americas.  “We observed DO levels of 29 ppm in water temperatures of roughly 90 degrees Fahrenheit. Not only did we achieve our highest level of DO, but our crop yields increased between 20 and 50%.”

Moleaer is also pleased to announce that it is collaborating with Hort Americas to commercialize Moleaer’s nanobubble generators within the hydroponics industry.  “We are excited to work with Chris and his team at Hort Americas to accelerate the commercialization of our nanobubble technology,” said Nick Dyner, CEO of Moleaer.  “Hort Americas brings a wealth of knowledge in helping growers utilize best-in-class technology to optimize their growing operations, and we are confident that our nanobubble technology will provide growers a new solution to significantly increase yields within their existing facility.”

The nanoBoost is available in various flow rates and are fully encased in a durable, NEMA4-rated weather-tolerant PVC shell. The unit is self-cleaning and features plug-and-play installation with no moving parts, thus ensuring long-lasting durability with minimal maintenance. The generator can be configured with an integrated pump or retrofitted with a customer’s existing pump to maximize energy efficiency.

 

For more information about Moleaer Inc., visit http://www.moleaer.com

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What are the optimum nutrient levels for hydroponic edible crops?

Trials with organic and conventional fertilizers in hydroponic production systems are showing it’s possible to produce edible crops at much lower nutrient levels.

How much different is it growing edible crops organically than it is with conventional production inputs? Hort Americas special projects manager Tyler Baras is studying the differences in trying to grow organically versus using conventional production methods.

Baras has been doing organic production research in a 12,000-square-foot greenhouse in Dallas, Texas, using four deep water culture ponds and a nutrient film technique system. The ponds measure 4-foot by 8-foot and are 10 inches deep. Baras said the ponds are smaller than what would be found in many commercial greenhouse operations, but said the pond size is common in vertical farm setups. Baras has been trialing commercial organic fertilizers including Pre-Empt and an experimental organic fertilizer. The organic fertilizers are being compared with crops grown with Hort Americas 9-7-37 hydroponic fertilizer with calcium nitrate and magnesium sulfate. All of the production systems have also been incorporated with the commercial microbial inoculant TerraBella. Crops being grown in the production systems include Italian basil, green butterhead and red butterhead lettuce.

Trials in Hort Americas demonstration greenhouse are comparing the growth of butterhead lettuce and Italian basil using organic and conventional fertilizers in hydroponic production systems.
Photos courtesy of Tyler Baras

Rethinking optimum nutrient levels

Baras said the deep water culture production results he has gotten with Pre-Empt organic fertilizer have been comparable to the crops grown with the conventional Hort Americas hydroponic fertilizer.

“With Pre-Empt we have been able to match the growth rates of the conventional salt fertilizer,” Baras said. “As a result of the growth rates we have gotten with the organic fertilizer, we have started to question the nutrient recipes that have been recommended for hydroponic edible crop production. Many of the traditional recipes for hydroponic production have a target level of 200 parts per million nitrogen. But we are seeing the same growth rates in the organic fertilizer ponds with 10 ppm nitrogen as the 200 ppm nitrogen conventional fertilizer pond.”

Baras said the electrical conductivity level in the organic fertilizer ponds has been as a low as 0.5 compared to 2.5 in the conventional fertilizer pond and the crops are coming out nearly identical in terms of production time and plant weight.

One difference between the organic- and conventional-grown crops is the time in propagation.

“The crops are finishing at the same time from transplant to harvest time, but we are keeping the plants an extra week in the seedling stage for the organic fertilizer,” Baras said. “We are running the seedlings for two weeks with the conventional fertilizer and about three weeks with the organic fertilizers.

“The organic plugs are started a week earlier, but they are transplanted on the same day as the conventional plugs. We want the roots coming out of the side of the plugs before we transplant them into the ponds. The seedlings are fairly similar in size when they are transplanted into the ponds.”

Plugs grown in organic substrates and fed with an organic fertilizer remain on the propagation bench one week longer than plugs receiving conventional fertilizer to ensure good root growth.

Once the organic and conventional plugs are placed into the ponds, they both spend the same amount of time there until the crops finish.

“The plants are coming out of the ponds with nearly identical weights,” Baras said. “Overall the seed to harvest time is faster with the conventional fertilizer, but that it is because we are able to transplant the plugs into the pond faster because the roots are coming out of the plugs sooner.”

Baras said the plants grown with the organic fertilizers have also shown they can be grown with lower levels of other nutrients. For example, with the conventional fertilizer the nutrient solution may contain 200 ppm potassium and the level is only 12 ppm with the organic fertilizers.

“Aquaponic growers have seen similar situations,” he said. “Some aquaponic growers may be running an EC of 0.7 with a relatively low nutrient level, but they are still seeing good growth.

We are seeing that as well with the organic fertilizers. There are low nutrient levels in the solution, but the crops are coming out the same and the leaf tissue analysis is nearly the same as well.

“For our trials the macronutrient uptake for the plants, even when they are grown in a low fertilizer concentration like 0.5 EC, they are still able to pull what they need out of the solution. Leaf sample analyses of butterhead lettuce and Italian basil grown in 0.5 EC organic fertilizer vs. 2.5 EC conventional fertilizer, most of the macronutrient levels in the leaves are very similar. It appears the plants are doing a good job of regulating the nutrient uptake to get what they need.”

 

Aging fertilizer solutions

Baras said letting the organic fertilizer solutions age in the ponds may have an impact on the availability of nutrients for some crops. The aging of the fertilizer solutions also has an impact on increasing the microbial population.

“We have definitely seen some differences in plant growth,” he said. “Our first crops of butterhead lettuce and basil did very well with Pre-Empt organic fertilizer. However, one of the other organic fertilizers we trialed grew a quality first crop of lettuce, but not the best looking basil. As we continued the trial with our second and third crops, the basil grown with the other organic fertilizer started doing much better. It appears the organic solutions in the ponds may need to age until the nutrients reach adequate levels.

“This is what we were seeing in a 9-month old Pre-Empt pond vs. a 2-month old Pre-Empt pond. A lot of nutrients have accumulated in the 9-month pond and are approaching the recommended nutrient levels that would be found in a conventional fertilizer system. Organic fertilizers like Pre-Empt don’t have a lot of magnesium in them. However, when the fertilizer is run in a pond system for 9 months the magnesium level rises and approaches what would be considered a conventional fertilizer target level for magnesium.”

Aging of the fertilizer solution also has had an impact on the root growth of the crops.

“When we compare how the roots look visually in the 9-month solution vs. the 2-month solution, the roots in the 9-month solution look much healthier,”Baras said. “The roots are very white, are longer and look really healthy and well-developed. There are also more roots on plants in the 9-month system.

“The root color is also significantly different. In the 2-month solution the roots look healthy, but there is some browning. They don’t have that crisp white look.”

 

Aging of the fertilizer solution can impact root growth. Plants (left) in a 9-month old organic fertilizer solution had more roots that looked healthy and well-developed compared to the root system of plants in a 2-month old organic fertilizer solution.

Rethinking optimum pH levels

Baras said he has been able to produce healthy crops in a pH range from as low as 4 up to 6.5.

“For hydroponic leafy greens the recommended pH ranges from 5.5 to 6.5,” he said. “We have basil and butterhead lettuce growing very well in organic systems at a pH of 4. On the other side of the pH range, I’ve heard of aquaponic growers growing these crops at a pH up to 7 without any problems. Based on our trial results some of the conventional recommendations for hydroponics for both pH and nutrient levels might need to be revisited.

“One of the biggest issues I see with hydroponic growers is overcompensating. For instance, they feel that they need to be constantly watching the pH. They may set up monitoring and dosing systems to ensure the pH doesn’t go below 6 or 5.5. They are investing in extra equipment because they think they need to keep the pH precisely in this range. It may be a case that the plants will do well outside this range.”

 

Impact on crop timing

Baras said one factor that could affect the optimum pH and nutrient range is the light level.

“If a grower is providing supplemental light, then the optimum pH and nutrient range may be different,” he said. “With the trials we are conducting we aren’t that far off from what most hydroponic growers are targeting for growth rates. Thirty-five days is a target number for a lot of lettuce growers. We have done 35-day crops. We want to be able to grow an organic crop in the same amount of time as a crop grown with conventional fertilizers.”

 


For more: Hort Americas, (469) 532-2383; info@hortamericas.com; https://hortamericas.com.

 

David Kuack is a freelance writer in Fort Worth, Texas; dkuack@gmail.com.

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Hort Americas attends 2017 Philly Indoor-Ag Con

Philadelphia Academy of Fine Arts, Philadelphia, PA

Focusing on community, innovation, and technology like A.I, The Philly Indoor-Ag Con brought together some of the leading experts in these areas to discuss Indoor Agriculture and how it is beginning to change the landscape of cities around the world. Philadelphia may be one of the most primed cities to welcome indoor and vertical farms alike with support from individuals like Mayor Jim Kenney who spoke at the event.

The conference was divided into 4 sessions covering CEA opportunity to develop local communities, how technology is changing the indoor farm business model, the coming impact of LED lighting, and AI in indoor ag. Each session had 3 speakers with a Q&A panel at the end of every session. Some thought provoking questions even had the panelists looking at things from new angles such as Mark Benoit of Bright Farms’ question: “What about thinking in terms of mouths fed too, instead of just jobs created?” I personally believe that “mouths fed” or “healthy calories consumed” will be a very important analytic in the future as automated approaches become more accessible due to advances in technology.

A common theme during the conference was the need to unite and standardize within this new industry. I agree with this central idea as we need to treat ourselves like any agriculture industry which uses standardization to decrease waste and increase profits. Eric Stein, one of the panelists, is looking to build a Center of Excellence for indoor agriculture to combat this issue. (If you are interested in participating in a brief survey to assist with the project please visit kennettindoorag.info)

One of the key messages from the conferences was the idea that technology is affecting business at a rapid rate, especially within CEA. Whether we are talking about the leaps and bounds made by LED every year or the tools of the grower becoming more of a key to success, Hort Americas is able to offer technical support that the emerging field will need to understand this ever changing source of light. As Xandar Yango of San’an Bio stated “LED will drive this industry.”

Esteban Macias of The Coalition for Sustainable Organics posed the question “How do you disrupt before you get disrupted?” I believe that the more we come together in a transparent manner for conferences and events like Philly Ag-con the more we can ensure that we will be the disrupters, not the disrupted. At Hort Americas we aim to not only have a high standard of quality and service in everything we do, but aim to supply the disruptive growers with products, tools, technology and supporting technical information they need to be innovative and maintain profitability; these products range from lighting to hydroponic substrates to traditional and organic fertilizer. Working together to address and fill needs, we should insure that they continue to grow well into the future.

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Breeding crops for controlled environment production

Controlled environment agriculture growers have been trying to fit a square peg into a round hole by growing field crops in indoor environments. This is changing as research tries to match plant genetics with the production environment.

During this year’s International Congress on Controlled Environment Agriculture (ICCEA) in Panama City, Panama, University of Florida horticulture professor and keynote speaker Kevin Folta discussed the overlooked reality that food crop varieties have not been bred for indoor controlled environment production.

“One of the limitations of controlled environment agriculture (CEA) is that the conditions do not match the genetics,” Folta said. “Plants being grown in CEA environments were actually developed for field production. There are a lot of opportunities that go unrealized by growing plants in a controlled environment. It’s like asking Chihuahuas to pull a dog sled. Plants that were bred for one application are expected to perform under very different applications. The genetics don’t match.”

Research has begun to develop the next generation of plants with the potential to develop different products using the same set of genetics by changing the environment.

Creating the next generation of plants

Folta said research has begun to develop the next generation of plants with the potential to develop different products using the same set of genetics by changing the environment.

“By flipping a switch and varying the light spectrum we could change green leaves to purple or have the plants accumulate specific flavors or textures or nutraceutical compounds,” he said. “That is all very realistic. This is like being able to shine a different light spectrum on a Chihuahua and turning it into an Alaskan malamute or a dachshund. A plant’s body, its composition, its chemicals, its secondary metabolites could be altered by changing the light environment. We need plants that are ready to do that. We need to identify or create those genetics.

“We are exposing plants to different light spectra and evaluating how the plants behave and perform. Then we will work with plant breeders to develop the next varieties.”

Varying the light spectrum has the potential to change leaf colors and textures and to have plants accumulate specific flavors or nutraceutical compounds.
Photos courtesy of Kevin Folta, University of Florida

Need for more industry involvement

Folta said the companies that are developing and manufacturing the lights for CEA production should become more involved with the development of plants grown in these environments.

“The lighting companies should be working with the university researchers and plant breeders,” he said. “The lighting companies should be financing the development of proprietary varieties. Unfortunately that hasn’t been an area of interest for the lighting companies. They want to make and sell lights. They forget the seed. The seed is a much more complicated machine.

“The lighting companies should be able to say to the growers here are the grow lights we are offering and here are the seeds that grow best under them. That opens up recurring revenue for the lighting companies. It behooves the lighting companies to focus on identifying plants that perform best with their products. It’s like saying that a Ford engine does best with a Motorcraft oil filter. It’s manufacturer’s optimized matching parts.”

Folta said plants are the most complicated part of matching the genetics with the environment and the part that people worry least about.

“It doesn’t matter whether the breeding company or the lighting company takes the initiative to develop the genetics,” he said. “This is going to happen whether it’s private plant breeders, universities or technology companies. This is another niche to create new genetics. You’ll see people filling this void.”

Researchers are learning that green, far red and UV light have important roles to play in controlled environment agriculture plant production.

Limiting, changing the production environment

Even technology companies like Panasonic, Toshiba and Fujitsu are finding opportunities in controlled environment agriculture.

“These types of companies will develop the genetics or will find the genetics that work well in CEA environments,” Folta said. “For now the field genetics will continue to be put in artificial conditions and the indoor environment will be reshaped to accommodate the plants. What should be done is finding or developing plants for these energy-efficient, artificial conditions that are sufficient to support growth. Research needs to be done to determine how to maximize output or yields with fewer photons of light or colors of light. Research is going to focus on economic viability. I expect the pharmaceutical companies will get involved in this research.

“My interests are much more about food and how we create the next generation of profitable growers and higher nutrient crops that are more readily available for consumers. That’s what gets me fired up.”

While matching the genetics to fit the environment is important, Folta said researchers also need to be looking at limiting the environment.

“At the same time that we are looking at the breeding and genetics, we are also looking at how we can deliver shorter pulses of light that still maintain the same output,” he said. “We have cut energy application by 50-80 percent and grown comparable products. The viability of these systems has come from people who have focused on the diminishing return of light efficiency. What they need to work on is the plant efficiency. That is something that is extremely viable.”

Folta said all of the research he has been focused on is with small format, high value crops, including lettuces, sprouts and microgreens.

“Our university does not have the facilities to conduct the necessary experiments,” he said. “But we are partnering with others to do that. We will have good access to larger spaces in the upcoming months. It’s less likely that this type of production would be done with crops that take more space like melons. We are looking at plants where the vegetative portions of the plants are eaten. If you consider a head of lettuce, every photon that is invested results in the plant structure. With a crop like tomatoes, 80-90 percent of the biomass is being thrown away or composted.

Kevin Folta at the University of Florida is interested in how to create the next generation of profitable growers and higher nutrient crops that are more readily available to consumers.

“Growing the plants in shorter production times, shorter supply chains, better postharvest quality because of shorter supply chains, possibly lower costs, a lower carbon footprint and access to local markets, these are the issues I want to address. I see this being done with lettuces, microgreens and herbs such as cilantro and basil. Not so much with corn or melons where a huge amount of energy is invested in a relative small return in terms of calories. These types of crops do better using the sun.”

Folta said 15 years ago people thought the idea of light recipes and changing the spectrum was a crazy and senseless idea.

“Researchers and light manufacturers thought mixtures of red and blue light were all that was needed to grow plants in controlled environments, so there wasn’t any concern about doing anything different,” he said. “Now people understand that green, far red and UV light have important roles and that light quality should change throughout the day. With that in mind, it gives us some flexibility when it comes to changing the production environment, which is a really good thing.”

 


For more: Kevin Folta, University of Florida, Horticultural Sciences Department, Gainesville, FL 32611; kfolta@ufl.edu; http://www.hos.ufl.edu/faculty/kmfolta.

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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2017 AVF Summit in Washington, D.C

By Kyle Barnett

The AVF Summit in Washington D.C was a great event to get a very eclectic group of people together that all want the same thing: to feed people and grow food sustainably as we move into a future that is rapidly growing and urbanizing.

University of the District of Columbia

Recent grads, farmers, politicians, and tech driven individuals all had a chance to discuss the future of vertical farming and urban farming including topics such as policy, certification, zoning, and the politics behind the future landscape of agriculture. The summit went into a lot of the bureaucracy surrounding urban and vertical farming and what it truly means to have a well thought out plan before you start growing.

Association for vertical farming

The day-long summit was separated into multiple sessions with presenters from across the urban farming and tech industries, including but not limited to Sonny​ ​Ramaswamy​ ​(The National Institute of Food and Agriculture), Dr​ ​Bob​ ​Whitaker​ ​(Produce Marketing Association), and Roberta​ ​Anderson​ ​(Global G.A.P.). Most sessions were accompanied by a Q&A panel of industry professionals, each having a unique perspective on the specific topic of that presentation. Starting with a focus on policy, followed by Standardization & Certification, and finishing the day with the politics behind The Farm Bill, the summit painted a broad picture of what the future farming landscape may look like.

Much like the summit, the future of farming will be a combination of many different subjects and professions, with different skills, opinions and knowledge uniquely coming together to create the way we grow and eat. Hort Americas is proud to support this diverse industry. Working with every type of farm from conventional to vertical, our goal is to assist the industry with not only superior equipment and supplies, but with technical expertise and hands on experience.

For more information on the Association for Vertical Farming, click here.

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AmericanHort technology tour to visit Hort Americas hydroponic research greenhouse

Tour of Hort Americas research and demonstration greenhouse in Dallas will show growers different hydroponic production systems for various vegetable crops.

Growers of hydroponic vegetables or those considering starting growing vegetables hydroponically should plan on attending the AmericanHort Production Technology Conference. Scheduled for Oct. 9-11 in Dallas, the conference begins with a Technology in Action Tour on Oct. 9 which will visit three local production operations: Hort Americas research and demonstration greenhouse, Seville Farms and Southwest Nursery.

 

All things hydroponic

Hort Americas, a horticulture and agriculture wholesale supply company, has retrofitted a 12,000-square-foot floriculture greenhouse for the hydroponic production of vegetable crops. Tyler Baras, who is the special projects manager at Hort Americas, is overseeing the trialing of five different production systems along with the testing of potential products for the company’s online catalog. The production systems include: nutrient film technique (NFT), deep water culture floating raft, a vertical hydroponic tower system, a flood-and-drain vertical rack system and a new capillary mat manufactured in Europe. The greenhouse is being used to grow a wide variety of lettuces, leafy greens, herbs and microgreens.

During the AmericanHort Technology in Action Tour on Oct. 9, Tyler Baras, special projects manager at Hort Americas, will be talking about the five different hydroponic production systems he is trialing.
Photos courtesy of Tyler Baras

The NFT system uses a new channel design. Baras said the narrower channels allow for the aging of crops without having to physically move plants from nursery channels to finishing channels.

Hort America’s main floating raft deep water system is an in-house custom design that measures 32-feet by 28-feet.

“We have tried using a Venturi system to incorporate oxygen, but for the last two months we have been doing trials with compressed liquid oxygen,” Baras said. “We have been doing trials to see how plants respond to increased levels of dissolved oxygen. This deep water system hasn’t been flushed in over a year.

“We have been managing the nutrient solution with water tests and individual salts. Instead of using a standard N-P-K fertilizer like we have been using in the other production systems, we have really focused on water tests and making nutrient adjustments based on those tests. We have been trying to keep the nutrients within a target range and trying to run the system for as long as possible without having to flush any of the nutrient system. We are testing for all of the essential nutrients. We are also looking at sodium chloride levels and seeing how those accumulate. Also, we are tracking what essential nutrients accumulate over time and how we can adjust the fertilizer being added to accommodate the natural accumulation in the system.”

In addition to trialing crops in different hydroponic production systems, Tyler Baras is also studying a variety of crops grown with conventional and organic substrates and fertilizers.

 

Baras is also studying how the water source can contribute to the nutrient level.

“We are considering how source water may be a limitation to applying this no-flush technique,” he said. “Our source water is municipal water, but it has a high sulfur content of about 44 parts per million. So we are looking at cutting out all sulfur inputs. We are learning the challenges of trying to manage a no flush system.”

In addition to the main deep water system, Baras said tour attendees will also see several smaller deep water culture systems.

“In these smaller deep water culture systems we will be showing the use of three different organic fertilizers where we are comparing the growth between them,” he said. “We will also be showing a smaller scale deep water culture system receiving aeration compared to one with no aeration.”

 

Vertical production systems

Another hydroponic system that Baras is working with is a vertical tower commonly used by smaller growers.

“We have a lot of customers who use this system so we decided to install one in the greenhouse so we could look at some of the issues that they are dealing with,” he said. “We also were looking to answer some of the questions that our customers had about using the system. An example is can this system be used to grow organically? We’ve done both organic and conventional trials with this system.

“We’ve also been looking at what crops perform best in this vertical system. We’ve done a lot of variety trials as well as with the other systems we’ve installed.”

Hort Americas is also trialing a vertical Growrack from Growtainer.

“This is a flood-and-drain vertical rack system,” Baras said. “The rack has three levels, but it could be expanded. The rack has a 2-foot by 5-foot footprint. We have equipped it with GE LED lights. This would be the type of system used in a vertical farm setup.”

Although the Growrack hydroponic system can be used to grow full size crops, Tyler Baras is using it primarily for seedling propagation.

Baras said the Growrack system, which is set up in the greenhouse, has done well in warm conditions because its water reservoir is below the rack.

“The reservoir is usually stored underneath the racks so it is in shade,” he said. “The water isn’t always in the trays so it doesn’t collect the heat from the trays. It works well in warm climates.”

Although Baras has grown full size crops in the Growrack, it is being used now primarily for seedling propagation.

“The focus of the system is how it has enabled us to cut back on the amount of space that is needed for propagation,” he said. “We can easily grow enough seedlings in this system for a 10,000-square foot greenhouse.

“The system is also being used by a Central Market store in Dallas to finish crops for its Growtainer farm. We helped consult on the management of the system and showed store officials how it could grow crops from start to finish in the same Growracks. The store is growing fully mature butterhead lettuce and basil in the system. This system can definitely work in indoor vertical farms.”

Baras said he has grown both organically and conventionally with the Growrack system.

“We have done organic seedling propagation in it,” he said. “We have used a variety of conventional and organics substrates and fertilizers with it.”

 

LED studies

In addition to trialing LED lights vs. natural light for greenhouse seedling propagation and crop staging, Baras said he is also looking at using LEDs supplemental light throughout the production of butterhead lettuce in the floating raft system.

“We are looking at how LED light affects leaf texture and plant morphology of butterhead lettuce,” he said. We are trying supplemental lighting during the summer. We are pulling shade so the light isn’t very intense. It appears that intense light can lead to tip burn that damages the plants leading to a poor quality crop. So we pull shade cloth and then run a prototype high-output LED grow light provided by GE for almost 20 hours. We deliver a low intensity of light over a longer period so we can provide the plants the light they need without stressing them. We are trying to improve the quality by adding LED light in order to produce more compact growth that is associated with LEDs.

“Under greenhouse shade cloth the lettuce leaves look fragile. We are trying to grow the lettuce to hit a certain weight. If the plants are grown under shade they look fairly large and floppy and the head doesn’t have the right density at its core. By using the LEDs we can produce the more traditional morphology where the plants have a dense core. The leaves aren’t floppy and the plants look more like traditional butterhead should look.”

 

Matching plants and production systems

Baras said he is trialing a wide range of crops in all of the production systems he is using.

“Primarily we are focused on lettuce and basil, but we are trialing a lot of varieties,” he said. “We definitely see some systems are capable of growing some varieties that other systems are not. We want to be able to recommend what varieties grow best in what systems. We are preparing a book based on our research that will include an entire section on strategies for how to use these production systems. We will provide example situations in the book discussing location, climate, market, what crops are being requested by that market and how to use that information to determine what production system is most appropriate.

“We are looking at primarily butterhead, romaine and oakleaf lettuce and 20 different basil varieties. We are also doing trials with arugula, spinach, cilantro, kale, chard, Asian greens and microgreens. We are doing an extensive study of herb varieties. There are also some unusual crops like stevia, wasabi arugula, celeriac and sorrel. We are determining all of these plants growth habits in the different production systems. This information will be in the book along with the details and nuances of growing each crop.”

A vertical hydroponic tower commonly used by smaller growers has been installed to answer some of the questions that Hort Americas customers have about using the system.

Based on the trial results, Baras said the book will provide details on each plant variety and its performance in each system.

“The book will provide information on the growth a grower should expect in different environments based on the amount of light and temperature,” he said. “The book will offer projected production numbers a grower should be able to reach. These will be realistic targets for each of the production systems we have studied.”

 


For more: Hort Americas, (469) 532-2383; https://hortamericas.com.

 

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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GLASE consortium aims to improve greenhouse energy efficiency

Even though the Greenhouse Lighting and Systems Engineering (GLASE) consortium is New York-based, the research it is doing has the potential to impact controlled environment agriculture worldwide.

The Greenhouse Lighting and Systems Engineering (GLASE) consortium is a partnership between Cornell University in Ithaca, N.Y., and Rensselaer Polytechnic Institute (RPI) in Albany, N.Y. The consortium will be conducting research to improve controlled environment agriculture (CEA) operations including reducing energy consumption.

 

 

The goal of the consortium is to create a more sustainable and profitable greenhouse industry. Although the focus of the research will be on greenhouse production, the findings should also have application to indoor CEA production including vertical farms and warehouses. Greenhouses, which can be electricity-intensive depending on the level of automation, cover 720 acres in New York State. The consortium is looking to reduce greenhouse electricity use and concomitant carbon emission by 70 percent and to increase crop yields by 2030.

Erico Mattos, who was appointed executive director of GLASE in June, said he has been hired as a subcontractor by Cornell University and will be working to recruit industry members to join the consortium.

“Currently I have a 50 percent time appointment with GLASE,” Mattos said. “My time with GLASE will increase as we bring in industry members. I am living in Georgia, but will be moving to upstate New York over the next year and will be located between RPI in Albany and Cornell University in Ithaca.”

Mattos said GLASE is a seven-year project which has received $5 million from the New York State Energy Research and Development Authority (NYSERDA). The money will be used to sponsor research between Cornell and RPI.

“The team leaders who will be doing the research are Neil Mattson at Cornell University and Tessa Pocock at RPI,” said Mattos. “They have a set of more than 300 milestones that their teams have to reach. They have already achieved some of these milestones.”

The research activities include improving lighting fixtures and systems that synergistically control lighting, ventilation, humidity and carbon dioxide, improving CEA operations and reducing energy consumption to create a more sustainable and profitable greenhouse industry.

“The teams at Cornell and RPI are well equipped with the resources they need to achieve the milestones of the core research proposal that has been sponsored by NYSERDA,” he said. “Even though the teams led by Neil and Tessa are completely self-sustainable, they may require some outside partnerships to achieve some of the goals.”

The GLASE consortium is headed by researchers Tessa Pocock at Rensselaer Polytechnic Institute and Neil Mattson at Cornell University and GLASE executive director Erico Mattos.
Photo courtesy of GLASE

Mattos said in his role as executive director he will act as an intermediary between Cornell, RPI and NYSERDA making sure that the research is proceeding and that milestones are being completed on time.

“The most important part of my position is to create a consortium with industry members,” Mattos said. “The goal over the next seven years will be for the project to receive less money from NYSERDA and more money from industry members. We want to establish a consortium that is self-sustaining. By bringing in industry members we will have money to do our own-sponsored research, technology transfer, outreach, and market research, all these types of things and GLASE will be self-financing.

“My role as executive director is to ensure that the team moves in this direction. By bringing in industry members, offering them the project and making sure that we provide them with access to the technology that is developed by Cornell and RPI.”

 

Complementary research

Mattos said the research that will be done at Cornell and RPI is complementary and will not overlap.

“RPI will be doing more engineering-related research, such as looking at light fixtures and components including the drivers and controllers,” he said. “They are also looking at photobiology—how plants respond to different spectra as they grow and produce different nutritional compounds and changes in plant metabolism and morphology. The RPI research work is more engineering-related.

“The research at Cornell is going to be more applied in the greenhouse, such as interactions of carbon dioxide enrichment and lighting control studies. Cornell will implement some of the systems that have already been developed at Cornell. Cornell will also be looking at different systems and different crops. Initially the studies will be done with tomatoes, lettuce and strawberries and then will be extended as necessary.”

 

The research conducted at Cornell University will be more applied in the greenhouse, including carbon dioxide enrichment and lighting control studies.
Photo by Chris Kitchen, Cornel Univ. Marketing

Mattos said the research will be expanded to commercial size greenhouses in New York, which will be 6,000 square feet for a small scale greenhouse and 20,000 square feet for a large scale greenhouse.

“RPI will develop new systems and Cornell will implement the greenhouse tests and then move forward to a final demonstration,” he said.

Mattos said the researchers will also be working in partnership with A.J. Both at Rutgers University, who will be doing some of the energy efficacy and radiometric studies of the light fixtures.

“One of the milestones Cornell research associate Kale Harbick will be working on is modeling,” Mattos said. “This will involve trying to calculate in advance how much energy in a greenhouse is consumed and what happens if some of the variables are changed. The research will look at how these changes affect the general energy consumption of the greenhouse.”

 

Seeking industry support

Mattos said when GLASE was developed over 30 industry companies provided letters of support indicating they wanted to become part of the consortium as industry members. Since the consortium was started, many other companies have expressed their interest in becoming part of the consortium.

“Even though these companies signed letters of support that doesn’t mean they will all become consortium members,” he said. “Cornell and RPI are both already working in partnership with some companies to develop the core research. There is nothing official as industry members yet. We are looking to bring in other industry members and really make them a part of this consortium. We want to reach a broad range of industry members so this support could be both financial or it could be providing equipment to conduct the research. But the primary goal is to bring in financial support.”

Mattos said there will be a series of benefits that come with industry membership.

“They would pay for a membership and then they would get a series of benefits. We are now working with a marketing media company to promote the consortium and the opportunity for membership.

“We want to bring in large manufacturing companies, but we also want to address the other end of the spectrum and work with small growers. The growers will benefit the most from this research.”

 

Academic collaborators, information hub

Mattos said it is the intension of the consortium to expand with researchers from outside New York.

“We intend to establish future academic collaborations to develop new research projects partially funded by GLASE through industry membership funds and new research grants,” he said.

Another goal of GLASE is to create a hub for greenhouse lighting and systems engineering which includes the centralization of information.

“We will create a central database to indicate the academic research currently on-going in the U.S. (what, where and who) to facilitate the interaction between the industry and academia,” he said.

 

Impact on greenhouse, plant systems

The crops that are to be studied initially by Cornell and RPI researchers are tomatoes, lettuce and strawberries.

“These are commercially relevant crops,” Mattos said “I went to Ithaca and met some of the members of Neil’s team, including graduate students Jonathan Allred and Erica Hernandez and research technician Matthew Moghaddam, who have been working with tomatoes and strawberries. Lettuce is also one of the most commonly produced greenhouse crops.

“Part of the milestones that Tessa will be working on will be done in environmentally controlled growth chambers and growth rooms. Tessa does not have a greenhouse. Most of the research that she will be doing is related to photobiology. Everything that she will be doing has application to warehouse production even though she is not doing the research in a warehouse. This research will look at nutritional compounds and pigment production. The research in the growth chambers will be compared with greenhouse studies.”

The research conducted at RPI will be done in growth chambers and growth rooms, which should have application to commercial warehouse production.
Photo courtesy of GLASE

Although the RPI research is not targeted for commercial indoor farms, Mattos said the results could be used to support that type of production.

“The proposal is to reduce greenhouse crop production energy consumption by 70 percent in seven years,” he said. “The economic factor and the majority of the research will be looking at greenhouse systems and how to integrate them. Economically we are focused on greenhouses. But we will be doing studies in growth chambers that may have application to support indoor farm production.

“Tessa will be looking especially at biological efficacy. Everybody talks about the efficacy of the light fixtures themselves. A lot of people are looking at that. Getting less attention is the biological efficacy, which is if there is a different spectrum, the same amount of photons or micromoles, can have a different impact on plants. Not only the morphology, but also the pigments, the chemical pathways. This is the biological efficacy.”

 


For more: Erico Mattos, Greenhouse Lighting and Systems Engineering (GLASE) consortium; (302) 290-1560; erico.bioenergy@hotmail.com; https://glase.cals.cornell.edu.

 

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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Victor Loaiza Mejia joins the Hort Americas team

Hort Americas is proud to announce that Victor Loaiza Mejia has joined our team as the Technical Sales Manager for California, Oregon and Washington.  Victor studied agronomy in Mexico and did a year of study at Cal Poly San Luis Obispo in California. After graduating he worked for Koppert Mexico and for British American Tobacco. In 2005, Victor received his masters of science degree from Wageningen University in the Netherlands.

His new found specialties in greenhouse horticulture and controlled environment agriculture then took him to the Netherlands where he worked three years for Royal Pride Holland as a grower before he came to the United States and joined Eurofresh Farms in Wilcox, Ariz. At Eurofresh he worked as a production manager and later took over the final implementation of Priva FS. Eurofresh Farms was bought by Nature Sweet in 2012.

In 2013, Victor became one of the first urban growers when he became the lead grower at Gotham Greens in Brooklyn, N.Y. At Gotham Greens Victor wore many hats and helped manage all operational aspects of the business. Victor left Gotham Greens after three years and moved back to California.

Victor has extensive experience in growing leafy greens and tomatoes under very varied production circumstances. He has worked with all types of software and has hands- on experience in organizing labor.

Please join us in welcoming Victor to Hort Americas.

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The impact of transplanting times, light exposure on hydroponic crop production

How quickly hydroponically-grown lettuce and leafy greens seedlings are transplanted and their exposure to LED light during propagation can impact crop production times.

Most growers using traditional hydroponic substrates transplant lettuce and leafy greens seedlings as soon as the roots reach the bottom of the plugs. This usually takes from seven to 10 days.

“We are trying to see if we can go far longer in Stage 1, which is this seedling stage,” said Tyler Baras, special projects manager at Hort Americas in Bedford, Texas. “Stage 1 occurs in a propagation area.

“Some growers incorporate an intermediate phase (Stage 2) which is a growing out stage. Stage 2 might consist of nutrient film technique (NFT) channels closely spaced next to each other or a deep water raft system with high density spacing. Generally a 2-foot-by-4-foot raft holds 72 plants or more. Both Stage 2 and 3 occur in the final growing out system. During Stage 3 those same NFT channels are spaced further apart or in a deep water system the plants in a 72-count raft are transplanted to a lower density 28- or 18-count raft.”

Some hydroponic growers incorporate an intermediate Stage 2 during which nutrient film technique channels are spaced close together.
Photos courtesy of Tyler Baras

Baras said holding the seedlings in Stage 1 for a longer period would reduce the amount of time that is required in the final Stage 3.

“This would actually be a two-stage system with an increase in time the seedlings are in the propagation stage or Stage 1,” he said. “Our reason for doing these studies is to see if we can eliminate the labor required to transplant the plants from Stage 2 to Stage 3, but still achieve yields similar to three-stage systems. Three-stage systems generally achieve more crop turns per year than two-stage systems. For many small growers trying to find enough labor and high labor costs can be major issues. If we can reduce the amount of labor required by extending Stage 1 this could help growers.”

Baras said the reason most growers don’t try to grow the seedlings longer during Stage 1 is the chance for root damage that can occur when the plugs are transplanted into the final production system.

 

Most growers are concerned root damage may occur when plugs are transplanted into the final production system if they hold seedlings too long in Stage 1.

“If seedlings are held too long, especially in a sheet substrate where there isn’t any divider between the plants, the roots can easily grow into the neighboring plugs,” he said. “When a grower goes to transplant the plugs and tries to pull them apart damage can be done to the roots. When the plugs are transplanted into the final system this root damage can lead to stunting and leaf dieback. The damaged leaves are more susceptible to disease pathogens and can attract fungus gnats. The plants will also require additional cleaning at harvesting to remove damaged leaves.”

Baras has observed the problems caused by holding the plugs longer in Stage 1 occur more often with transplanting into NFT systems than with deep water raft culture.

 

Promising results

Baras said that he has conducted several trials with different substrates holding the seedlings in Stage 1 up to six weeks.

“We have gone the longest with self-contained plugs,” he said. “This is usually with organic production where there is slower growth. We have pushed the seedlings for a longer period of time. So far the best results with conventional hydroponic production are at about three weeks. With organic production it’s around four weeks because the plugs are self-contained and the roots don’t grow into neighboring plugs.

“We are pushing some of the seedlings to nearly a month and not seeing significant leaf dieback or stunting from root damage. We are shaving off several weeks within the final production system. It’s still possible to damage the seedlings if they are held in Stage 1. We are seeing the upper limit is higher for deep water culture than it is for NFT.”

 

Impact of LED lighting

Baras said another factor that can impact seedling development is exposure to supplemental light.

“We have been trialing different photoperiods and light intensities,” he said. “We have found that the light treatments that we give the seedlings can actually affect whether the plants produce more roots or more leaves. We are looking at the differences between exposing the seedlings to sunlight and LED light from GE Arize Lynk fixtures and different photoperiods.

“Depending on the lighting treatment we can create a smaller plant on top but increase root mass. This allows us to grow the seedlings longer without the plant canopies growing into each other. When the seedlings are removed for transplanting there is no damage to the leaves. There are more leaves left intact by growing more compact plants. We are still able to get a lot of root development.”

One of the most exciting findings that Baras is seeing is the increase in final weight of lettuce given LED supplemental light.

“When we started our research we were using traditional production methods,” he said. “We would sow the butterhead lettuce seed and place the trays under sunlight and then transplant the seedlings between seven to 14 days. With this traditional growing method we would produce a 6-ounce head. With the adjustments that we are making to staging and using LED lighting we are producing 8-ounce heads in the same amount of time. We are very excited about that. We think it is one of the most significant things coming out of our research greenhouse right now.

“The plants grown with LED light are finishing with 2 ounces more of plant weight. This seems to be related more to light quality and the influence that it has on the seedlings’ morphology than on total light received. It is not like the plants are receiving a lot more light when they are exposed to LEDs instead of sunlight. The morphology of the plants is completely different because of the light quality spectrum they are receiving. We now want to look further at light quality treatments during the seedling stage. This includes different ratios of blue/red LEDs, the inclusion of different colors and checking for variety specific results. There are still a lot of trials to do.”

 

Butterhead lettuce seedlings lit with LED lights during propagation are producing larger heads in the same amount of time as seedlings exposed to sunlight during propagation.

One of the trials that Baras wants to study further is varying the length of time the lights are on.

“We are also looking at how long the lights are on,” he said. “Whether there is a big difference depending on the length of the photoperiod. We have not found an optimum length of time. We have found that more light is not always better.

“We are looking at exposing the seedlings to 20 hours or 24 hours of light. Right now 20 hours of light is outperforming 24 hours of light. But 24 hours of light is outperforming natural sunlight. This is across all crops, including a couple varieties of lettuce and Italian basil.”


 

For more: Hort Americas, (469) 532-2383; https://hortamericas.com.

 

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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Nutrient guidelines for hydroponic tomato production

By Victor Loaiza, on behalf of Hort Americas

It is important to conduct water and nutrient solution analyses on a regular basis to ensure hydroponic tomatoes are receiving the proper level of nutrients.

Making sure that hydroponically-grown tomatoes receive the proper nutrient levels requires testing water and nutrient solutions. Growers also need to confirm that irrigation equipment is delivering the correct amount of fertilizer. Nutrient levels should be monitored and adjusted according to the crop developmental stage, the season, light levels and tomato type.

“In applying fertilizer to a plant grown either in soil or in a soilless medium, the goal is to match the nutrient uptake of the crop as closely as possible to the amount provided as fertilizer” (Mary Peet, USDA, Division of Plant Systems-Production, 2005). There are many reasons to do so, but a very important reason is to prevent fertilizer runoff which is actually money runoff.” For growers with open irrigation system this will hurt the most. In a closed irrigation system, excess fertilizer is recovered and recycled after water treatment.

Water sample analysis

It’s very important to regularly conduct irrigation water and nutrient solution (water + fertilizers) analyses. Irrigation water quality from a well, dam or municipal system should be determined before implementing any type of fertilization plan. Important levels growers should know include: water electrical conductivity (EC), water pH, sodium (Na), chloride (Cl) if using a municipal water source, calcium (Ca), magnesium (Mg) and sulfates (SO4). The preference is for low levels of all these elements. Water EC less than 0.5 millisiemens/centimeter (mS/cm) is a good level. If the water pH is high, a pretreatment can be done with sulfuric acid, phosphoric acid or citric acid. Optimum and safe pH levels are between 5 and 6.

Nutrient solution sampling should be conducted on a weekly or biweekly basis. Nutrient solution sampling should be taken from two sources:

1. Feed is the nutrient solution the irrigation system is pumping to the plants sampled at the dripper.

2. Drain is the leachate coming from the substrate. This is critical to a fertilization strategy.

Useful information

The information obtained from the nutrient solution analysis helps to:

1. Verify the irrigation equipment is dosing the correct amount of fertilizer.

2. Verify the EC and pH of the nutrient solution are satisfactory levels.

3. Determine the amount of fertilizer by element being absorbed by the plants.

4. Determine the amount of fertilizer that needs to be added/subtracted from the nutrient solution.

It can be determined if the amount of irrigation is appropriate by looking at the drain EC. If the EC is too high, there may not be enough water being applied to the plants. If the EC is too low (lower than the feed EC) plants may be receiving too much water.

5. Verify if the amount of irrigation is appropriate by looking at the drain EC. If the EC is too high, there may not be enough water being applied to the plants. If the EC is too low (lower than the feed EC), plants may be receiving too much water.

There are many laboratories that perform this type of water and nutrient solution analysis. It is important to choose a lab where the staff has experience in hydroponics.

Two recommended laboratories are Groen Agro Control in the Netherlands and Perry Laboratory in Watsonville, Calif.

Recommended nutrient levels

A Netafim fertilizer controller unit

In the photo of the Netafim crop management technology fertilizer dosing unit, the blue line on the left is the irrigation water (well water or municipal water with no fertilizer). This water is pumped to the mixing chamber where fertilizers are injected and the water becomes the nutrient solution (pink line on the right). The nutrient solution flows through EC and pH sensors to make sure that the target EC and pH are maintained.

Table 1 shows the nutrient levels by element or molecule recommended for tomato nutrient solutions measured at the drain. Elemental levels at the lower or higher margins are not necessarily bad. Maintaining the proper nutrient level is crop dependent.

Table 1. Nutrient solution elements in drain water

Table 1 reflects the desired values obtained by a drain sample analysis. By constantly analyzing the nutrient solution, the target levels can be matched that best suits the crop.

Preparing nutrient solutions

The most common chemicals for mixing nutrient solutions are mentioned in the Hort Americas article on hydroponic greenhouse pepper production.

They include:

  • Ca(NO3)2 (Calcium nitrate)
  • KNO3 (Potassium nitrate)
  • KH2PO4 (Mono-potassium phosphate)
  • MgSO4*7 H2O (Magnesium sulfate)
  • H3BO3 (Boric acid)
  • MnCl2*4 H2O (Manganous chloride)
  • CuCl2*2 H2O (Cupric chloride)
  • K2SO4 (Potassium sulfate)
  • MoO3 (Molybdenum trioxide)
  • ZnSO4*7 H2O (Zinc sulfate)
  • Fe Sequestrene 330 (iron chelate)

General recommendations

  • Some tomato varieties are more susceptible to blossom end rot (BER) http://ucanr.edu/sites/placernevadasmallfarms/files/86509.pdf) than others. Check irrigation strategy and nitrate levels since high nitrates could be the cause of BER.
  • Keep daily irrigation measurements in a logbook (EC, pH and drain percentage). This is a daily task that should be performed early in the morning before the irrigation cycles start. See handheld EC/pH meters https://hortamericas.com/product-category/growing-supplies/meters/
  • Compare the manual EC/pH readings with the irrigation unit readings, they should match.
  • Keep K:Ca ratio close.
  • Calibrate pH and EC meters once a week.
  • Calibrate pH sensors on the irrigation unit at least once a month.
  • Keep the irrigation system clean and flush it periodically.
  • Clean fertilizer tanks every month to avoid fertilizer sedimentation.
  • Keep the pH of the micronutrient stock tank low (pH 4).

 


 

For more: Hort Americas, (469) 532-2383; https://hortamericas.com.

 

Here are some of the fertilizers Hort Americas offers:

 

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Be aware of the challenges of using loose substrates in hydroponic production systems

If you’re going to use a loose substrate in a hydroponic production system, you may have to change how you handle starter plants and the treatment of recycled water.

Many growers of ornamental plants including annuals and perennials traditionally use a peat-based substrate such as 70 percent peat, 30 percent perlite. The growers, who produce these crops in containers, will often use the same substrates if they expand their crop offerings to include hydroponically-grown edible crops, including lettuces and leafy greens.

“There are some growers who use these peat-based substrates in hydroponic production systems, but it is more difficult to manage because hydroponic systems need to run clean,” said Tyler Baras, special projects manager at Hort Americas in Bedford, Texas. “Debris from these loose substrates can lead to clogging of irrigation lines in hydroponic systems like nutrient film technique (NFT). In the case of a deep water culture floating raft system the goal is to flush the system as infrequently as possible because there is so much water involved. Growers want to keep both of these hydroponic production systems fairly clean.

“The loose substrates used by traditional bedding plant growers can break apart so that there is some peat and perlite floating in the system or sinking to the bottom of the pond or water reservoir.

Debris from loose substrates like peat and perlite can lead to clogging of irrigation lines in hydroponic systems.
Photos courtesy of Tyler Baras

Baras who recently completed trials with loose substrates in a 12,000-square-foot research and demonstration greenhouse in Dallas said the more commonly used substrates for hydroponic systems are inert materials. These include preformed plugs, such as stone wool plugs or cubes, polyurethane foam blocks, stabilized medium like synthetic polymer peat plugs and wrapped plugs which can have an outside coating like Riococo Closed Bottom Organic Plugs.

Focused on root growth

In the greenhouse trials that Baras is doing with lettuces and basil in NFT and deep water raft systems, he is studying the differences between peat and coir.
“Coir has more water retention from what we have seen,” he said. “It really depends on the production system, the growers’ staging strategy and how the seedlings are watered. There are a lot of factors that are similar and they both have the possibility of being used for hydroponic production.

“Coir is often used as a substitute for peat. Often when coir is used, growers have to change their irrigation strategies. Fine coir holds more water than peat. Once the seed has germinated and is at the seedling stage the goal is to establish a strong root system regardless of the substrate used. The plug should be dominated by roots. As long as the plug has a large enough root mass once it is transplanted into a hydroponic system, there is a good chance for success.”

Seedling plugs transplanted into a hydroponic system should be dominated by roots regardless of the substrate used.

Growers should consider young plant development strategies specific to the substrates they are using.

“An example would be plugs with some type of wrapping around the outside,” he said. “The bottom is open, but the plants should be grown until there are enough roots to cover the bottom of the plug so it doesn’t fall apart once it is placed in the hydroponic system.”

Limited choice of organic substrates

Baras said growers doing organic hydroponic production have a more limited selection of substrates.

“Growers who want to grow organically can’t use stone wool, foam blocks or any polymer peat plug,” he said. “Organic production is generally limited to loose substrates. This would include loose peat- or coco-based substrates and coco plugs. There aren’t a lot of options.

“If a loose substrate is used and some of it is falling apart and into the production system it can quickly clog the irrigation system. It’s important to have a solid root structure before transplanting the plugs into an organic hydroponic system.”

Although organic production is generally limited to loose substrates, the Riococo Closed Bottom Organic Plug offers an alternative stabilized medium.

Whether growing organically or not, when using loose substrates in hydroponic systems, Baras said growers need to have a good filtration system.

“Anything coming off the tail end of the NFT channels is going to have to be run though some kind of filtering stage to collect any debris before the water goes back into the reservoir,” he said. “The irrigation lines are usually ¼-inch or smaller and those can clog quickly when loose substrates like peat or coco are used.”

 


For more: Hort Americas, (469) 532-2383; https://hortamericas.com.

For more information on choosing a substrate for hydroponic production systems, https://hortamericas.com/grower-resources/growing-media-and-substrates/

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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Nutrient recipe for hydroponic greenhouse bell peppers

Bell peppers grown in greenhouse hydroponic systems follow similar environmental requirements as tomatoes and eggplants. It is a common production practice to leave all the leaves on the pepper plants. This creates very tall walls of foliage that slightly affect the plants’ nutritional requirements.

Pepper growth follows generally two different phases during greenhouse production. After the seedlings are transplanted, the first six weeks of production is geared toward developing a strong vegetative base. After fruit set, the nutrient recipe is changed slightly to keep the plants in balance. For peppers only potassium is significantly increased after fruit set occurs.

Table 1. Nutrient solution for hydroponic pepper cultivation.

0-6 weeks Mature crop
Reference EC 2.2 mS/cm 2.5mS/cm
Nitrate (NO3) 200 ppm 180 ppm
Ammonium (NH4) 7 ppm 15 ppm
Potassium (K) 240 ppm 270-300 ppm (200 ppm*)
Phosphate (PO4) 50 ppm 50 ppm
Calcium (Ca) 220 ppm 200 ppm (300 ppm*)
Magnesium (Mg) 50 ppm 45 ppm
Iron (Fe) 1.5 ppm 1 ppm
Manganese (Mn) 0.55 ppm 0.55 ppm
Zinc (Zn) 0.33 ppm 0.33 ppm
Boron (B) 0.3 ppm 0.3 ppm
Copper (Cu) 0.05 ppm 0.05 ppm
Molybdenum (Mo) 0.05 ppm 0.05 ppm
Sulfates (SO4) 20 ppm 20 ppm
Chloride (Cl) <300 ppm <300 ppm
Sodium (Na) <100 ppm <100 ppm

Concentrations in parts per million (ppm) at the dripper. Micronutrients are in shaded boxes. (*) See below for explanation on blossom end rot.

 

Like all nutrient recipes the numbers in Table 1 are a starting point that will need to be adjusted depending on the local environment (temperature, humidity, solar radiation and water quality) and the different salt accumulations that occur in normal conditions depending on the absorption by any given strain of pepper. Note that the ammonium (NH4) levels for young and mature plants are very low compared to nitrates. Ammonium is not necessary depending on the substrate included for pH buffering.

Note also that chloride and sodium have upper ranges. These two are considered contaminants even if they have nutritional value for the plants. They are generally present in the water and their requirements are very low similar to micronutrients.

 

Preventing blossom end rot

Bell peppers’ most common physiological problem is blossom end rot, which is generally due to a water stress preventing the internal transport of calcium. It is common to increase the concentration of calcium ions in the solution together with chloride, phosphate and boron while reducing potassium to promote the absorption of calcium during potential blossom end rot periods, particularly during hot summers (* in Table 1).

 

The most common chemicals for mixing nutrient solution are the following:

Ca(NO3)2 (Calcium nitrate)

KNO3 (Potassium nitrate)

KH2PO4 (Monopotassium phosphate)

MgSO4*7 H2O (Magnesium sulfate)

H3BO3 (Boric acid)

MnCl2*4 H2O (Manganous chloride)

CuCl2*2 H2O (Cupric chloride)

K2SO4 (Potassium sulfate)

MoO3 (Molybdenum trioxide)

ZnSO4*7 H2O (Zinc sulfate)

Fe 330 – Sequestrene (chelated iron)

Commonly in hydroponic production, chemicals are mixed in concentrated solutions to be diluted at the time of irrigation. The drawback of this fertilization method is that some of the chemicals present will precipitate out and be removed from the nutrient solution and need to be kept separate in at least two reservoirs. As a common rule, calcium needs to be separated from phosphates and sulfates to prevent precipitation.

 

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Are you maintaining the proper oxygen levels in your hydroponic production system?

Growers have affordable options for ensuring plants receive sufficient oxygen in hydroponic production systems to maximize growth and to reduce the chances of disease.

 

Oxygen is critical in the development and growth of edible crops grown in hydroponic systems such as nutrient film technique (NFT) and deep water raft culture. Tyler Baras, special projects manager at Hort Americas, is studying methods of adding oxygen to both conventional and organic hydroponic production systems in the company’s 12,000-square-foot research and demonstration greenhouse in Dallas, Texas.

“One of the big differences is how growers add oxygen,” Baras said. “A lot of times in conventional hydroponics, growers use air pumps and air stones to add oxygen. In organic systems these tend to be hot spots for biofilm development. We have removed all air pumps and air stones from the organic systems we are trialing.

Tyler Baras, special projects manager at Hort Americas, is studying methods of adding oxygen to both conventional and organic hydroponic production systems.
Photos courtesy of Tyler Baras

 

In the conventional production systems Baras is studying he has installed water pumps with a Venturi attachment to add oxygen to the nutrient solution reservoir.

“The pumps aren’t injecting air into the irrigation lines, but simply into the reservoir to circulate the water and to create a circular flow within the fertilizer reservoir,” he said. “As the pumps operate they draw in air through a ¼-inch emitter. There is the benefit of moving around the solution and the air being drawn in increases the level of dissolved oxygen.”

A method that organic growers use to increase oxygen levels is cascading the water when it returns to the reservoir. As water returns it is allowed to fall and break the surface of the reservoir so that the water can pull in oxygen.

“This can also be done in vertical farms where the water will fall down large return pipes to the reservoir,” Baras said. “This can happen in multiple stages where the water will drop several times. This is an effective method for increasing dissolved oxygen.

“For NFT, it appears more oxygen can be delivered to plant roots when the flow rate is increased per channel. As the flow rate increases, more oxygen is delivered to the roots so water isn’t sitting in the channel as long. This allows freshly oxygenated water to be delivered quickly to the roots. In conventional hydroponic NFT systems the flow rate is about ½ liter per minute. In our hydroponic NFT system I have been aiming for about 1-2 liters per minute.”

 

Adequate oxygen levels

Baras said oxygen is necessary for plant roots to perform metabolic processes.

“Most of the water uptake in plants is passive,” he said. “But there is a stage where the plants use energy to actively pull up water through the roots. This requires oxygen. If there isn’t any oxygen in the root zone no water will make it up through the roots to the top of the plant. Low oxygen in the root zone can appear as wilting at the top of the plants. This can seem counterintuitive in a hydroponic system because the roots are sitting in water, but the tops of the plants look like their wilting if there isn’t any oxygen in that water.”

As the flow rate increases in a NFT system, more oxygen is delivered to the roots so water isn’t sitting in the channel as long.

 

Baras said the need for oxygen in an organic hydroponic system is even more important because of the presence of living microbes in the fertilizer solution reservoir.

“These microbes also require oxygen,” he said. “The oxygen demand is often higher in organic systems than conventional systems because not only do the plant roots need oxygen, but the microbes need oxygen as well. In an organic hydroponic system one of the best ways of keeping biofilm in check is to keep the beneficial microbes happy.”

Baras said most of the oxygen measurements he has been taking in his research have been showing very similar oxygen levels for both conventional and organic production systems when the crops are performing well.

“I have been aiming for a level of 7-12 parts per million (ppm) dissolved oxygen, but generally the readings fall between 7-9 ppm,” he said. “I’m using a ProODO meter from YSI that is a very sensitive piece of equipment that accurately measures dissolved oxygen.”

Although most hydroponic growers are concerned with maintaining adequate oxygen levels, Baras said if too much oxygen is added to the solution it can cause root stunting.

“I haven’t reached that threshold yet in my trials,” he said. “It’s crop dependent on what that level is. When there is too much oxygen the roots have less motivation to grow larger because they are getting everything they need with a smaller surface area. That can then translate to the plants producing less biomass resulting in less leaf tissue. So at some point too much oxygen can actually cause less growth. For crops like tomatoes, peppers and cucumbers the whole plant would be stunted.

“The only way growers could reach excessive oxygen levels that damage the plants are when liquid oxygen or possibly ozone is used. Using air pumps or air stones to add oxygen, the levels won’t be high enough to stunt plant growth. To reach higher oxygen levels of 15-16 ppm, a grower would have to use other methods like liquid oxygen and ozone. It’s very difficult to reach high oxygen levels above 10 ppm unless an alternative method is used beyond air pumps, Venturis and cascades. I haven’t seen any growers go much higher than 8-9 ppm using the conventional methods.”

Baras said growers using a deep water raft system could try increasing turbulence in the pond to increase oxygen level. However, too much turbulence can sometimes cause damage to the roots.

Increasing turbulence in a deep water raft system can increase the oxygen level. But too much turbulence can damage roots.

 

“The roots in the turbulent areas are the ones that often times grow poorly,” he said. “The plants that are near the irrigation outlets where the currents are stronger, they have the poorest root growth. Sometimes growers will use air pumps in their ponds and those plants directly above where the air stones are located grow poorly.”

For more: Hort Americas, (469) 532-2383; https://hortamericas.com.

 

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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Calling CEA Enthusiasts

Experienced growers are in demand, and you can accelerate your indoor and greenhouse growing know-how at the University of Arizona Controlled Environmental Agriculture Center [UofA-CEAC] in Tucson, Arizona from June 5th – 12th, 2017 at our Hydroponic Crop Intensive Workshops.

Grab a vine and swing into the CEAC Greenhouses for what that the industry considers “a critical service in training tomorrow’s greenhouse experts [that] no other university within the USA can provide the same quality and expertise of service” – Wadsworth Controls.  This is the last opportunity in 2017 to attend both courses back-to-back to optimize your time away from home and increase your grower know-how under the direction of our hydroponic research specialists.

CEAC Intensive Workshops are intended for growers looking to quickly advance their skills as they relate to hydroponic tomato and lettuce cultivation.  These multiple day events feature over a semester’s worth of real university course content, hands-on work in the greenhouse, useful agenda items such as an engineering roundtable discussion, face-to-face time with experts on your special questions, and networking time with personal follow-ups.

 Why CEAC’s Hydroponic Intensive Workshops?

  • Education immediately meets application – CEAC’s unique facilities support a quality learning experience, where knowledge from classroom lectures is immediately applied in the greenhouse.
  • Substantial time for immersion – The length and thoroughness of CEAC intensive workshop is unmatched.  Tomato Intensive includes 4 ½ days & Lettuce Intensive includes 3 ½ days of instruction and training.
  • Experience yields efficiency – CEAC Intensive Workshops have been around for 10 years.  We’ve constantly improved the content and its delivery, based on feedback, in order to more effectively disseminate knowledge. With a database of 100’s of common questions and strategic delivery of content, we’re likely to address your questions naturally throughout the course.  In addition, the limited class size offers the opportunity to address some questions more specific to your operation.
  • Bigger questions?  Better answers! – Between the instructors, supporting faculty, and members of the Round-Table Greenhouse Design discussion, you can pick our specialist’s brains and pull from their tens of thousands of hours of real-life experience with hydroponic growing systems.

Registration is open but space is limited.  Reserve yours now and take advantage of savings when you register for the combined workshops!

More information on the course, instructors, registration, designated lodging, and a list of topics covered can be found on the Controlled Environment Agriculture Center’s website here:

http://ceac.arizona.edu/hydroponic-crop-intensive-courses

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Industry survey seeks information on hydroponic food production

Researchers at Michigan State and Iowa State Universities are looking for feedback from hydroponic food growers to help them determine where research is needed to benefit the industry.

If you are doing hydroponic food production or thinking about doing this type of production, your input is needed. Controlled-environment agriculture (CEA) production researchers Roberto Lopez and Kellie Walters at Michigan State University and Chris Currey at Iowa State University have developed a survey to gain a better understanding of current hydroponic food production practices. The researchers will also use the results of the survey to help determine future research projects as well as their extension efforts.

Kellie Walters, a PhD graduate research assistant at Michigan State University, is conducting a hydroponics industry survey to see where she can make the biggest impact with her research.
Photo courtesy of Mich. St. Univ.

 

 

“One thing we like to do as researchers is to see where we can make the biggest impact,” said Kellie Walters, who is a PhD graduate research assistant at Michigan State. “We want to know what matters to growers. What would they like to see done? Some of the information collected from the survey might impact the research I will be doing for my PhD. I have already set up some experiments working with some of the environmental parameters that we ask growers about in the survey.

“One of the things that I am interested in is the environment, including temperature, carbon dioxide, light intensity and quality, how these interactions affect the growth and flavor of different herbs and leafy greens. In the survey we asked about the value of crop flavors. I want to know if growers really care if their crops are more flavorful.”

 

Determining production protocols

Walters is working with Michigan State horticulture professor Roberto Lopez, who is her major advisor for her PhD degree.

“Kellie did her master’s degree with Chris Currey at Iowa State where she focused on hydroponic herb production,” Lopez said. “Now she is doing her PhD with me and she is going to focus on hydroponic leafy greens production in greenhouses and indoor controlled environments.

“We wanted to survey the industry and determine production protocols for growers. So we are asking questions related to where they grow hydroponically—in a greenhouse, hoop house, indoors or outdoors? What types of systems are they using? What crops are they growing? Even though we are focusing much of our research on leafy greens, we wanted to find out what food crops are being grown currently. We wanted to determine growers’ inputs as well as their cultural and environmental parameters. This includes their water source, temperature set points, and if they provide supplemental or photoperiodic lighting. Also, do they grow young plants for hydroponics or are they basically just finishing the crops?”

Michigan State horticulture professor Roberto Lopez said the hydroponics industry survey will provide researchers with information about growers’ production protocols.
Photo courtesy of Mich. St. Univ.

 

Lopez said the survey results will help determine the direction of his, Walter’s and Currey’s research.

“The survey will impact the way Kellie does her research and the direction of her research as well as for Chris,” Lopez said. “The survey will help to determine the major needs of hydroponic growers.”

 

Determining production challenges, research needs

Currey said the survey offers the opportunity to find out what challenges are occurring with hydroponic growers.

“There are so many more growers out there than I will ever have the chance to personally interact with whether that is with a phone call, through email, or visiting their facilities,” he said. “When I talk to growers and get to know them and learn what they are doing, I learn about their problems. It’s helpful to have all of those perspectives. It’s good to get a view of the landscape and the challenges that exist.

“Even before we did the survey we knew that growers were having certain issues with lighting and temperature, so we have been working on those. Productivity under low light or productivity under cool temperatures and coming up with predicative models for growth. There are certain things we know growers could use. Hopefully we are already focusing our research programs on some of those. The survey will hopefully validate the need for some of the research we have already been doing. The survey will also help us to plan research in the future to make sure that it is relevant and needed.”

Iowa State University horticulture professor Chris Currey is working primarily with leafy greens and herbs, which are generally a more accessible crop for growers beginning to do food production.
Photo courtesy of Iowa St. Univ.

Currey said most of the research conducted as a result of the survey results will likely be done using nutrient film technique or deep water raft systems.

“I work primarily with leafy crops, mainly herbs and greens,” he said. “Our facilities are well-suited for leafy crops. It takes a little more of a specialized facility for vine crops like tomatoes and cucumbers because of their dimensions. I also work on the leafy crops because I think they are generally an accessible crop for growers to begin food production. The barrier to entry with leafy greens can be a little lower than with tomatoes with respect to some of the learning curves. Leafy greens also have shorter crop times for ornamental growers who are looking for fast crops. Leafy greens could be a short “gap” crop rather than something like tomatoes which can be a six- to nine-month crop.”

Currey said he is also hoping the survey helps to identify growers’ needs that also compliment his skill set as a researcher.

“I expect there will be comments and questions about powdery mildew management on lettuce or some other pest issues,” he said. “There are other people aside from myself who are better equipped to conduct powdery mildew research. Hopefully the survey results will give ideas to other researchers as well. We want to make the results publically available. The survey might give other researchers ideas about what needs can be addressed with their skill sets.”

Walters said they will be publishing the results of the survey to give the industry access to the information.

“There is no way that we can create the optimal guidelines for growing all of the hydroponic crops growers are producing,” she said. “The survey will help other researchers know what areas growers would like to focus on and to help inform growers of issues other growers are currently facing.”

The Hydroponics Industry Survey consists of 24 questions and should take less than 10 minutes to complete. The deadline for participating in the hydroponics survey is Friday, May 12.

For more: Kellie Walters, Michigan State University, Department of Horticulture, East Lansing, MI 48824; kelliew@msu.edu. Roberto Lopez, Michigan State University, Department of Horticulture, East Lansing, MI 48824; rglopez@msu.edu; http://www.hrt.msu.edu/people/dr_roberto_lopez. Chris Currey, Iowa State University, Department of Horticulture, Ames, IA 50011; ccurrey@iastate.edu; https://www.hort.iastate.edu/directory/christopher-j-currey.

Editor’s note: This month Kellie Walters  was selected as a 2017-2018 Future Academic Scholars in Teaching (FAST) Fellow.

 

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

 

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Organic vs. traditional hydroponic production: the top 3 differences

When it comes to changing from conventional to organic hydroponic production methods, there are three main areas that growers find most challenging.

Tyler Baras, special projects manager at Hort Americas in Bedford, Texas, said growers are increasingly inquiring about organic hydroponic production. Baras is running hydroponic production trials comparing organic and conventional production methods in a 12,000-square-foot research and demonstration greenhouse in Dallas.

“We’re doing the research because of market demand,” he said. “A lot of growers are getting feedback from their customers that they would prefer to have produce that is certified organic. Produce suppliers and brokers hear from the grocery stores and then they bring those requests to the growers.

 

Tyler Baras, special projects manager at Hort Americas, is comparing organic and conventional hydroponic production methods using a variety of edible crops.
Photos courtesy of Tyler Baras

 

“We don’t necessarily believe that produce grown with organic production methods is superior. We believe in conventional production methods as well. What we are trying to do is provide as many options to our customers as possible.”

Baras said that organic production is a whole system that includes substrates, fertilizers and pest management. But most of the questions coming from growers about organic production are related to fertilizers.

 

  1. Inoculants and tank culturing

Baras said an advantage of traditional fertilizers is all of the research that has been conducted on them has enabled growers to target exact nutrient profiles for specific crops.

“Research has enabled traditional fertilizers to come down to fairly exact levels,” he said. “Growers are able to figure out exactly how many parts per million of each nutrient they want to put into nutrient solutions. The chemistry allows them to be that exact.

“Organic fertilizers are a little trickier because there isn’t the precision targeting each nutrient. Generally there are inputs that are going to have several nutrients in them. Growers don’t have the ability to adjust individual nutrients as easily.”

Another issue with many commercial organic fertilizers is they are animal-derived. These organic fertilizers include manures, bone meal, blood meal and feather meal.

“These animal-based organic fertilizers don’t mix well with water,” Baras said. “If growers are using recirculating hydroponic systems, these animal-based fertilizers tend to start going rancid and smell in a few days. These fertilizers can also form a sludge that can clog irrigation lines and emitters.”

Baras has focused his research trials on Pre-Empt, a plant-derived organic fertilizer which has blackstrap molasses as its major component. He has been comparing organic vs. traditional fertilizers in several hydroponic production systems, including flood-and-drain grow racks, two different nutrient film technique (NFT) systems, deep water culture floating rafts and a ZipGrow Tower system.

“We have successfully grown butterhead lettuce and basil in all of these systems using organic inputs,” he said. “We have several other crops that we are running through these systems in smaller trials, including spinach, cilantro, arugula, strawberries and other lettuce and herb varieties. Most of research is still focused on butterhead lettuce and basil.

“We currently don’t have any trials going with microgreens, but some of our first trials were with microgreens under LED lights using organic substrates and organic fertilizers. We definitely proved that is a viable production system.”

Baras said he knows of growers using Pre-Empt organic fertilizer who haven’t flushed their nutrient solution tanks for five months.

“The key is the slow development of the fertilizer tank,” he said. “Some growers have immediately added the organic fertilizer to their reservoir at full strength and they quickly notice that their tank starts to foam at the top and starts to smell similar to what happens with animal-based organic fertilizers. We’ve found if an initial charge, about half the target rate, is added first, along with a microbial inoculant at the same time, these issues can be avoided. We are using Terra Bella as the microbial inoculant because it has an extensive profile of different microbes.”

Baras said the half rate of fertilizer and microbial inoculant are run through the system for about two weeks.

“Once the microbial population becomes established, the nutrient solution in the tank can be brought up to full strength without any foaming or odors,” he said.

 

  1. Nutrient solution pH management

Baras said one of the major issues with the organic nutrient solution during the first two weeks is pH swings.

“The pH of the nutrient solution on the first day the organic fertilizer is added to the tank is in a good range around 6-6.5,” he said. “Within a couple days of adding the fertilizer, the nutrient solution pH shoots up to around 8.0. There are a lot of plants that do not like a high pH. Iron-inefficient crops like basil have a hard time taking up iron at a high pH. There will be a lot of chlorosis at the top of the plants. This happens within a couple days of the pH going above 7.

“During the second week the pH drops to between 4 to 5. The plants continue to grow, there are a lot of nutrients in the solution, but the quality is very different. During the third week the pH stabilizes. As the microbial population stabilizes, the pH stabilizes around 5.5-6.5, which is ideal for leafy greens.”

Baras said growers have taken two routes to stabilize the nutrient solution pH.

“There are growers who will let the solution go for this two-week swing and let the solution stabilize similar to what we have been doing,” he said. “Other growers are trying to control the pH with inputs. When the pH goes up they will add citric acid. When the pH starts to drop they will add sodium bicarbonate.

“The inputs to adjust the pH are very limited. The main downfall with citric acid is that it is anti-microbial. So although a grower is able to lower the pH, it’s not good for the microbial population. Another option is vinegar, but most commercial growers are using citric acid for controlling pH for organic production.”

Baras said the options for raising the pH are also limited.

“Growers would like to use potassium bicarbonate, but potassium bicarbonate is not allowed for pH management under the organic rules,” he said. “Potassium bicarbonate can be used to control powdery mildew, but it can’t be used to control pH in the nutrient solution tank. What growers are left with is sodium bicarbonate or baking soda. The pH can be raised, but over time sodium accumulates. Once a certain threshold of sodium is reached then problems start to occur including nutrient disorders.”

Baras said another issue with using citric acid and sodium bicarbonate for pH management is the longevity of the nutrient tank solution is shortened.

“It could be a couple months, but at some point the sodium levels are so high that either the whole solution or part of the solution is going to have to be dumped,” he said. “The tank is going to have to be flushed. The amount of citric acid and sodium bicarbonate added can be done in small increments, but it is the accumulation that causes problems.”

Baras said once the nutrient solution stabilizes, the swings in pH won’t be as drastic when additional water and fertilizer are added to the tank.

Another option for controlling pH includes adding more water or fertilizer.

“Depending on the water source, adding water to the tank can sometimes raise the pH,” Baras said. “Also, the Pre-Empt fertilizer is somewhat acidic and that could be used to lower the pH simply by adding more fertilizer.”

 

  1. EC targets and nutrient analysis

Baras said growers who switch to organic production systems should continue to measure the electrical conductivity (EC) of the nutrient solution to determine soluble salts levels.

“A lot of the nutrients in organic fertilizers won’t register on EC readings because of the forms they are in,” he said. “They aren’t yet broken down into simple salts. If growers are basing their feedings solely on EC readings, the EC of the nutrient solution will probably read much lower even when sufficient nutrients are being provided to the crop.

“The specific makeup of the nutrient profile, how many parts per million of each nutrient, for organic and conventional fertilizers are not the same. I don’t target the same nutrient profile for an organic nutrient solution that I do with conventional nutrient solutions.”

 

Butterhead lettuce and basil have been grown successfully in Hort Americas’ research greenhouse using several hydroponic production systems and organic inputs.

 

 

Baras said plants are fairly flexible on many of the nutrients, which can be maintained within a fairly wide range.

“With organics, sometimes the calcium level may only be 100 parts per million where with conventional fertilizers the target calcium level for most leafy greens is around 200 ppm,” he said. “But even at 100 ppm calcium with an organic fertilizer, we are not seeing the issues that we would expect from having a low calcium level.”

Baras said for fruiting crops like tomatoes, calcium can be an issue with organic production.

“Calcium sulfate is an amendment that can be used to correct calcium deficiency,” he said. “Another nutrient that can be low with plant-based organic fertilizers is magnesium. What we have found is nutrients like calcium and magnesium that are usually lacking in the organic fertilizer we are using, they are generally found in the source water of most growers.

“In our research greenhouse the source water contains 30 ppm magnesium and 30 ppm calcium. Those can make a fairly significant contribution to the nutrient solution, especially with calcium that isn’t taken up as quickly as other nutrients. Over time the calcium level accumulates in the fertilizer tank. As the organic nutrient solution is used over several months, the calcium level rises and nearly reaches the conventional target of 200 ppm calcium. Like calcium, magnesium generally rises over time with source water contributions.”

 

Measuring changing EC levels

Baras said that he uses an EC meter to get an estimate of the soluble salts level in the organic nutrient solution.

“For lettuce the EC of the nutrient solution in the greenhouse for conventional production is usually run at 2-2.3,” he said. “For organic lettuce production I typically run an EC between 1.2-1.6. I make sure that the crop has the nutrients close to the target range by sending water samples to a testing lab to get an exact analysis. But even that has some issues with organic production.

“I’ve found that the amount of time a nutrient solution sample sits after it is sent out can affect the nutrient analysis from the lab. Since nutrient solution microbes are constantly active, changes can occur within the sample. Initially a sample sent to a lab may have 100 ppm nitrogen. But a few days later the same sample may indicate there is 150 ppm nitrogen.”

Baras has sent the same samples to multiple labs and he has received analyses with significant variations, especially with nitrogen. He suggests growers stick with one lab.

“If there is a lab that is relatively close to a grower’s operation, this can help ensure that results are returned relatively quickly,” he said. “The best practice is for growers to create their own archive of the nutrient analyses so that they can compare test results to previous notes. Lab test results are likely mimicking what is happening in the nutrient solution tank. The microbes’ activities are also affected by temperature the solution is stored at as well. The readings could come out higher or lower.

“There are different factors that can affect the EC including the temperature and the crop stage when a water sample is taken. Crop age, whether plants are young or mature, whether there is a well-developed root system along with the crop itself, impact the interaction with the nutrient solution. These can affect the form the nutrients are in and how that would read out on a nutrient analysis.”

Baras said how often an EC analysis should be done depends on how large the reservoir is and how often water is added to the reservoir.

“A small reservoir that is frequently amended with water should be tested fairly often,” he said. “Nutrients can quickly accumulate in a small reservoir. Growers with a small reservoir might be testing every week. With a large reservoir used for deep water culture that may contain 8,000 gallons of water, it is not as urgent to test as frequently.”

For more: Hort Americas, (469) 532-2383; https://hortamericas.com.

 

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

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Pre-Empt FAQ

pre-empt-organic-fertilizer

We have been receiving a lot of questions about Pre-Empt. He are some responses to the common questions:

pre-empt-organic-fertilizer

When is Pre-Empt appropriate?

It is best suited for recirculating hydroponic production of leafy greens. It can be used as a direct substitute for conventional fertilizers in NFT, DWC/Floating Raft, and Flood & Drain. When used properly, it won’t clog 1/4″ emitters which is very rare for an organic fertilizer.

When is Pre-Empt not appropriate?

The cost may be prohibitive for drain-to-waste systems. We do not have any experience with the product being used in aeroponic or aquaponic systems.

Can Pre-Empt be used for tomatoes?

Yes, but…
-Growth may be overly vegetative and not as reproductive as standard commercial tomato formulas
-Blossom end rot will likely be an issue on larger varieties like beefsteaks
-Works well with grape and cherry tomatoes but still may have overly vegetative growth
-Calcium may be supplemented with an organic solution grade gypsum

What amendments would you suggest to use with Pre-Empt?

-Organic solution grade gypsum and silica may be used to reduce tip burn or blossom end rot
-Inoculants like TerraBella can help reduce biofilms and improve nutrient availability

How do I inoculate a tank with beneficial microbes?

Fill a 5 gallon bucket with water and add 1 oz molasses. Let water sit for 1 day to remove chlorine (unless using RO or distilled water). Add 2 oz. of TerraBella and let sit for 1 day before adding to reservoir. This is enough to inoculated 300 gallons of nutrient solution.

How often should I change the reservoir?

This is going to vary a lot depending on growing environment, system, water source, and fertilizer rate. In general, using a water source with a very low EC and keeping the fertilizer rate low will help extend the life of the reservoir. Some growers flush their system once every 4-5 months and some growers flush every two weeks. The cost to build a reservoir with Pre-Empt may be up to 100x more expensive than conventional fertilizers so it is very important to reduce the frequency of flushes.

What EC should I maintain?

This will depend on source water EC and crop. The target EC is generally going to be lower than the EC used with conventional fertilizers. Generally leafy greens are grown at an EC ranging from .8 up to 1.6. It is best to start low to avoid the development of biofilms in the system

What pH should I maintain? And how?

I’ve seen growers completely ignore pH while using Pre-Empt. The pH may fluctuate from 4.8 up to 7.5 without noticeable effect on the crop. I’ve also seen growers maintain pH levels with citric acid and sodium bicarbonate.

How consistent is Pre-Empt from batch to batch?

There is variability in the product and it is possible that a batch may perform differently than previous batches. This variability is generally minimal enough that growers do not need to adjust practices.

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Why should you attend the International Congress for Controlled Environment Agriculture 2017? – Part 2

As I posted earlier this month, I have been fielding a lot of questions from industry peers asking why Hort Americas continues to support, sponsor and have a booth at the 2nd International Congress on Controlled Environment Agriculture (ICCEA). This event is scheduled for May 17-19, 2017, in Panama City, Panama. I thought the best way to respond was to write a two-part blog. In my first post I focused on my business reasons for participating in ICCEA. In this second post I will focus on my philosophical reasons for my involvement with ICCEA.

Education is the foundation for innovation

I firmly believe in education. I believe that kids who have access to the best educational opportunities have a huge head-start.

I believe those young adults who are fortunate enough to attend and disciplined enough to commit themselves to a college education give themselves the opportunity to develop skills and have experiences that provide them with advantages over their peers. Business people committed to constantly challenging and questioning themselves on what they think they know through continuing education have the opportunity to be the leaders and innovators who reshape their perspective industries.

This is why I am committed to ICCEA. ICCEA is about education. ICCEA is about bringing together the best and brightest minds so that they can share their research and experiences. ICCEA is committed to expanding the knowledge base of its attendees. Each of these attendees will return to their businesses knowing they are armed with the best base of horticultural science information currently available.

For those of you who know me, my commitment to education as the base for a solidpersonal and professional foundation should not surprise you. For those of you who don’t know me, I ask that you visit the Hort Americas website, read the back issues of Urban Ag News and their blogs. You will quickly realize that my companies and I are not only committed to continuously educating and learning, but also to supporting those committed to horticultural and agricultural extension services.

Networking is an opportunity to explore

Whenever you meet successful business people, they usually have a diverse network of professional associates. This should not be a surprise as part of their success is their vast network of knowledgeable colleagues and friends. These networks allow them to easily navigate the business challenges and obstacles they encounter daily.

Because “good” networking leads to opportunities that create success for both parties these relationships are often long lasting and they (at least in my case) lead to some amazing friendships. This is another reason I firmly believe that networking is not selling.

Networking is listening and learning. Networking provides assistance when opportunities present themselves. In some cases these opportunities lead to sales, but effective networking does not have to lead to a business transaction.

How networking has impacted me

I credit education and networking with putting me where I am today professionally (and personally.) There are many people responsible for making me who I am today. In addition to my family and friends, many of the people I credit with helping me develop as a horticultural professional I met at educational events throughout my career. Three of these industry colleagues (and friends) will be at ICCEA this year:

1. Dr. Don Wilkerson, Texas A&M University horticulture professor and extension specialist emeritus

I met Don when I was a young “professional” more concerned with having a great time over anything else. Unfortunately I cannot share the stories of my younger years, and hopefully Don won’t either. But, that simply shows you how good of an educator Don is.

Unknowingly Don was able to communicate commercial horticultural issues in a way that made it easy for me to understand. More importantly Don inspired me to ask questions that I sought the answers for.

2. Dr. Toyoki Kozai, professor emeritus and chief director, Japan Plant Factory Association Center for Environment, Health and Field Sciences at Chiba University

Dr. Kozai graciously opened himself up to an American who had never been to Japan. I had a long list of questions for him and I was eager to learn anything and everything I could about vertical farming. Whether the questions were from me or anyone else I have seen Dr. Kozai interact with, he always takes the time to answer every question, no matter how elementary, with respect and care.

3. Dr. Chieri Kubota, professor, University of Arizona, The School of Plant Sciences, Agricultural and Biosystems Engineering

A former student of Dr. Kozai, Chieri likely does not know this, but I totally enjoy visiting with her. Not because she is always willing to share new facts and figures based on her research, but because she is so excited about her work that she inspires me to continue to be passionate about our industry.

After reading the two blogs I have prepared on ICCEA it should be obvious why Hort Americas will be attending this industry event in Panama City, Panama, on May 17-19, 2017. During this conference we will be there learning from leading horticulture researchers, networking and creating opportunities with government representatives, existing agricultural/horticultural businesses, entrepreneurs and manufacturers of controlled environment agriculture products.

Look forward to seeing you in Panama.

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Why the International Congress for Controlled Environment Agriculture 2017? – Part 1

Recently I have been fielding a lot of questions from industry peers asking why Hort Americas continues to support, sponsor and even have a booth at the 2nd International Congress on Controlled Environment Agriculture (ICCEA). This event is scheduled for May 17-19, 2017, in Panama City, Panama. I thought the best way to respond was to write a two-part blog posting. In my first post I will focus on my “business” reasons and in the second post I will focus on my philosophical reasons.

Business opportunities in developing markets

As we all know, “the only constant is change.” This is no different in the world of commercial agriculture and production horticulture regardless of geographical locations. Panama and other Latin American countries have a very strong and proud history in agriculture and horticulture, which due to changing weather patterns are being forced to adapt. As one would expect, these changes will not come easy and will cause many farms, of all sizes, to suffer in the process. If these same farms want to continue operating and more importantly want to continue to be profitable, they will need to find a new way. My belief is that controlled environment agriculture (CEA) can and will be one of the tools that help these farms redefine themselves.

CEA is a technology-based approach to food production. The aim of CEA is to provide protection and maintain optimal growing conditions throughout crop development. Production takes place within an enclosed growing structure such as a greenhouse or building.

Panamanian government officials feel the same way. They have shown and continue to show a commitment to helping the country’s farmers.

The government’s support started in 2015 and 2016 when it committed and put to work approximately $100 million USD towards investments in innovative production techniques and strategies. In January 2017 the government announced a first-round monetary infusion of $243 million USD for fiscal year 2017 to be directed toward increasing food production using controlled environment/precision agriculture. These funds will be used to transition from current traditional agriculture and its challenges, including water, inputs, available arable land, to technology-based food production which includes CEA.

Panama funds CEA projects

Hort Americas has seen Panama’s government funding put to work. In the last 18 months the following projects have either been initiated or implemented.

* 10 Greenhouses of various sizes built with all the necessary equipment/technology.

* 2 Indoor farm food production facilities (one currently in development stage).

* 1 New university research-and-development facility.

* 1 Tissue culture laboratory.

* 1 CEA seedling production facility.

* 4 Private research-and-development facilities to test indoor food production (agricultural companies).

The following projects are currently in the planning stage.

* 1 Large-scale, world class research-and-development facility (a combined private/government/university initiative).

* 5 Greenhouses (more possible with new incentives recently announced).

* 1 Indoor food production facility.

Panama is one of several Latin American countries receiving this type of financial funding to upgrade the agriculture sector. Peru, Chile and other countries are following suit. In addition, there is a robust effort by CAF Development Bank of Latin American, and other multilateral organizations to increase their agriculture portfolio throughout Latin America, applying technology to produce food.

Hort Americas’ customers are active in the production of food and flowering crops using the technology that best fits their region. From our perspective, and depending on the crops, CEA can be designed and built to suit a variety of crops, production methods and management styles. This can be done as a greenhouse, vertical farm/plant factory or tissue culture facility.

ICCEA does two things to support CEA. First, it focuses on the education needed to support crop production regardless of the technology or geographic region. Second, it brings together people with varied backgrounds, including international investors, growers/farmers, innovators and entrepreneurs.

Due to ICCEA’s unique program and approach it not only attracts attendees from Latin America, it also attracts creative and innovative minds from around the world. In 2015, Hort Americas was amazed to meet and develop working relationships with many new businesses from the United States and Canada.

Unprecedented opportunities for everyone.

ICCEA creates opportunities for people and companies to build business partnerships. And that is what we look for–opportunity. When people have access to information and science that supports what they are interested in, good things happen. When people have the opportunity to listen to leaders from their industry, good things happen. When people have the opportunity to share great food and drink, good things happen. When people have the opportunity and time to professionally network, good things happen.

In 2015, Hort Americas had the pleasure of meeting and starting new business relationships with many new people and companies from the USA, Canada and the Caribbean (arguably more developed markets.) These attendees represented a wide array of thought, businesses, hydroponic crops and experience. It was awesome. Based on conversations we are currently having, we see even more opportunities to meet new and existing customers in 2017.

So, once again Hort Americas will be attending ICCEA in Panama City, Panama, on May 17-19, 2017. We will be there learning from leading researchers, networking and creating opportunities with government representatives, existing agricultural/horticultural businesses, entrepreneurs and manufacturers of CEA products.

Stay tuned for part 2 and hope to see you there.

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Looking for a better, easier way to do greenhouse IPM?

Greenhouse Scout is an integrated pest management app that makes it easier to collect, store and analyze scouting data along with identifying insect pests and which beneficials can be used to control them.

Most greenhouse growers know the benefits of scouting their crops for pest insects and mites. Scouting can help to identify and minimize pest outbreaks, reduce plant damage and crop losses and save on pesticide and biological control costs.

Greenhouse Scout mobile app developed by the New York State Integrated Pest Management Program at Cornell University initially began as a how-to notebook for greenhouse ornamental plant growers.

“Incorporating beneficial organisms for insect and mite management in greenhouses is not something that growers can just jump into,” said Elizabeth Lamb, ornamental IPM coordinator at NYS IPM Program. “A lot of information is required for someone trying to successfully do biocontrol. Once it becomes part of the production system it can work, but getting started is the hard part. We didn’t see one good way of putting all of the information together in a relatively easily accessible format.

Elizabeth Lamb, ornamental IPM coordinator at NYS IPM Program, worked with GORGES Inc. to develop the Greenhouse Scout app.
Photos courtesy of NYS IPM Program

“We initially started putting the information together in a notebook. We said this is great, but we knew people weren’t going to carry the notebook into the greenhouse. When we started asking growers if they would like this as an app, something they could carry on their smart phones, we received a lot of positive responses. That’s how we decided to develop the app.”

Developing an interactive app

NYS IPM Program staff began working with GORGES Inc. in Ithaca, N.Y., to develop the app program. The funding to create the app came from a USDA National Institute of Food and Agriculture grant.

“The company asked me during the initial discussion if we wanted to make the app interactive so that is when we decided to add the scouting and record keeping functions. The app really has two applications. In addition to the scouting function, it’s a source of information for pests and pest identification and for beneficials identification and usage. Even if a grower is not using the app to collect scouting data, it can be used to identify common greenhouse pests like green peach aphid. The app will also determine what beneficials can be used, how to apply them and the environmental factors that need to be considered. All of that information is available on the app.”

Although the Greenhouse Scout app was developed for greenhouse ornamentals, it has application to other protected environment crops.

Lamb said that even though the app was initially developed for greenhouse ornamentals, it could be used with greenhouse vegetables and other protected environment crops.

“The app is specialized by insect pest,” she said. “Anyone who has these insect pests potentially could use the app. For the most part, many of the insect pests we see in ornamental greenhouses are also found in vegetable greenhouses. For vegetable greenhouses a grower could certainly use the app because many of the insect pests and biologicals are the same. We can also add new insect pests and beneficials as they become important.”

More effective scouting

Lamb said even though growers are good about identifying pest problems on their plants, they can have a difficult time tracking the data, especially from year to year.

“We are trying to help growers make scouting easier so that they will do a better job of scouting,” she said. “If a grower is walking through the greenhouse and sees something, he can easily take out his smartphone, go to the app and put that information in. If a grower is doing more organized scouting, the app can be set up to do scouting in specific locations. If there are multiple scouts collecting information all of that data can be inputted simultaneously.”

One of the biggest scouting gaps the app can help eliminate is determining the effectiveness of pesticide and/or beneficials applications.

“At the same time the app is used to note numbers of pest insects and beneficials, it can also be used to record applications of beneficials or pesticides,” Lamb said. “While the app does not include recommendations on what pesticides to use to manage a particular pest, those active ingredients labeled for New York State are listed.”

Although scouting information is being written down on paper or in a notebook, Lamb said having all of this data doesn’t indicate whether beneficials and pesticide applications are working.

“Growers might have a general idea if they are seeing fewer or more of a particular pest from the previous week,” she said. “The app offers growers the ability to look at the scouting data on graphs so they can see whether the pest numbers are going up or down. This gives growers more information to use in terms of deciding what to do.

“We are hoping to reduce pesticide applications by encouraging the use of biological controls. However, if growers are using the app to scout and are only applying pesticides, we would hope that they would also be able to reduce their pesticide use. Growers can use the app’s graphs to determine a pesticide’s effectiveness so that they don’t over apply. If a pesticide is not particularly effective, growers can come back and apply something else.”

Greenhouse Scout offers growers the ability to look at scouting data on graphs so they can see whether pest numbers are going up or down and whether a control application is effective.

Lamb said being able to print the graphs enables growers to keep a running record of what has happened with their crops in previous years.

“Growers can see if there is a pattern for a pest,” she said. “Whether a pest keeps coming in at the same time on the same crop. Growers usually remember those kinds of things, but it’s nice having a resource they can refer to to see what controls actually worked.”

Ease of use

Lamb said the app was designed to be used in all size greenhouses.

“If growers have an internet connection the recording of the scouting data to their computer is automatic,” she said. “If growers don’t have an internet connection in the greenhouse, the app holds the information until the connection is made. It doesn’t have to be plugged into something else. The data is synced directly into the computer. If there are four workers scouting simultaneously in different greenhouses, they can input data on the same account. Growers could sit in their offices looking at what is going on with pest management in all of those greenhouses at the same time.

“The only thing growers need to add is their locations. A location could be designated as Greenhouse 1, Section 1, Bench 1. In some cases growers move their crops around and five different crops may move through that area during the production season. In that case, it might make more sense to call a crop by its name such as pansies. Pansies may move from Greenhouse 1 to Greenhouse 2 and then they move onto sales. The intention was to make the app as flexible as possible. Growers can use the data from year to year if it’s something that makes sense for their operation.”

Lamb said she has received requests to translate the Greenhouse Scout app. She is currently working with GORGES to find out the costs involved with translating the app into Spanish and French. She is also working on apps for conifers and greenhouse hops that will include both insect and disease pests.

 

For more: Elizabeth Lamb, NYS Integrated Pest Management Program, Cornell University, Ithaca NY 14853; (607) 254-8800; eml38@cornell.edu; https://nysipm.cornell.edu.
NYS IPM’s Greenhouse Scout is available for $9.99 at the Android and iPhone app stores.

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.