Grodan launches the award-winning e-Gro software platform in North America

Empowering growers to make data-driven decisions for peak crop performance

Press Release – Grodan, part of the ROCKWOOL Group, has now launched e-Gro in the North American market. E-Gro is the ultimate software platform for data-driven Precision Growing, giving growers smarter insights into the greenhouse, allowing them to fully optimize cultivation. E-Gro was officially launched in the Netherlands during the HortiContact trade show in February of 2019 and was awarded the Concept Innovation Award at GreenTech in June 2019.


The more you know, the better you grow

In the greenhouse, the decisions you make today have a major impact on tomorrow’s results. Smart innovations like cloud solutions and Internet of Things applications are connecting the greenhouse, while AI learning and Big Data are allowing growers to level-up their cultivation. But, merging all these available tools and data to support decision-making is complex and time consuming. That is, until now. After the successful introduction of the e-Gro app, Grodan is taking the next digital step with the e-Gro software platform. e-Gro supports a grower’s knowledge, experience and growing strategy with valuable insights and smart recommendations based on the root zone, climate, crop and harvest data. Growers are in control, with 24/7 visibility into the greenhouse environment, anywhere and everywhere, empowering them to make informed decisions to maximize their harvest. 


Digital transformation in the greenhouse

With the e-Gro launch, Grodan is now at the forefront of the digital greenhouse transformation worldwide: data-driven cultivation via an intelligent software platform is now becoming a reality. E-Gro can be linked to the most common climate computer systems and is available for both smartphone, tablet and desktop.

Grodan has been at the forefront of crop optimization for 50 years, with a strong focus on precision cultivation, leading to greater efficiency, improved cultivation strategy and less impact on the environment. After the development and successful introduction of data-driven technologies in the greenhouse such as the Grodan Water Content Meter (WCM), the Grodan 6-Phase advice model and GroSens MultiSensor, the renewed e-Gro platform is the next step in data-driven Precision Growing. With e-Gro, Grodan is committed to further increasing the sustainability of the cultivation process.

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First Wheelchair Accessible Farm at Local Bronx Public School

Empire BlueCross BlueShield and Green Bronx Machine to Launch First Wheelchair Accessible Farm at Local Bronx Public School

Press Release – NEW YORK – Green Bronx Machine (GBM), a nationally recognized non-profit organization dedicated to helping students live happier and healthier lives, is partnering with Empire BlueCross BlueShield (Empire) to launch the first wheelchair accessible farm and teaching kitchen in America at P.S. 721x, a District 75 school in the Bronx dedicated to educating students living with disabilities.

Continue reading First Wheelchair Accessible Farm at Local Bronx Public School

Do you want to sell the freshest, most flavorful and fragrant cut basil?

How you grow and process fresh cut basil will impact the flavor and shelf life of the harvested product.

Basil is one of the most popular culinary herbs. Whether grown as a potted crop or for fresh cut sales, basil is an herb that’s in demand year-round. Growers looking to add edibles to their product mix should consider basil to be a must-have herb in their product offerings.

Continue reading Do you want to sell the freshest, most flavorful and fragrant cut basil?

Topclear: for a spotlessly clean greenhouse roof!

By Sudlac

Topclear is the perfect cleaner for removing Sudlac Eclipse® LD, Transpar®, Optifuse® and Optifuse® IR coatings. With this product, the grower decides when to remove the coating. Simply spray on Topclear, leave it to wash off in the rain, and you’ll have a clean greenhouse roof that allows maximum light into the greenhouse. This is particularly important in the fall and winter to ensure optimum growth, quality and fruit setting.


Continue reading Topclear: for a spotlessly clean greenhouse roof!

What are the benefits of applying greenhouse shading products?

Sudlac shading products give greenhouse growers of flowers and vegetables the ability to increase and extend production during periods of warm temperatures and high light levels.

High temperatures and high light levels, especially during the summer can have negative effects on ornamental and vegetable crops produced in protected structures, including greenhouses. An economical way for growers to reduce light and temperature levels is by applying shading products to greenhouse glazing materials.

Continue reading What are the benefits of applying greenhouse shading products?

Dissolved oxygen improves plant growth, reduces crop time

Incorporating dissolved oxygen into hydroponic production systems during warmer temperatures can help improve plant growth and reduce crop time.

Trying to grow hydroponic crops like leafy greens can be a real challenge during warmer times of the year. Growers have few options to lower temperatures, including cooling the greenhouse and/or water temperature. Another production technique that is being used by hydroponic growers in the United States and Australia is to introduce dissolved oxygen into the fertilizer tank solution.

“We’ve heard anecdotal reports that increasing dissolved oxygen levels can help prevent some root diseases like Pythium and other root rots,” said Tyler Baras, special projects manager at Hort Americas in Bedford, Texas. “We’ve also heard that increasing dissolved oxygen can possibly improve nutrient uptake and improve overall growth. Another possible benefit with using dissolved oxygen is reducing tip burn on leafy greens.

“These are some of the main issues with growing in warm climates like Texas during the summer. With an increase in water temperature comes a higher disease pressure and chances for tip burn. This has occurred in both nutrient film technique and deep water culture systems.”

Hort Americas conducted trials growing butterhead lettuce, basil and arugula in deep water culture systems at three different levels of dissolved oxygen.
Photos courtesy of Tyler Baras

The optimum water temperature for lettuce is between 65ºF-70ºF. For basil the optimum water temperature is around 75ºF.

Baras said most of the references he has read for adding dissolved oxygen suggest incorporating 4-10 parts per million for leafy greens.

“Most growers that I know are adding between 6-7.5 ppm for leafy greens,” he said. “When growers start to go beyond that rate to reach a higher level they have to use something like compressed oxygen or ozone. These are the main two methods, which are more expensive, for achieving a higher dissolved oxygen rate. Most growers I know are using a less expensive Venturi system or an air pump with air stones to add dissolved oxygen.”


Trialing different levels of dissolved oxygen

Baras has been studying the impact different dissolved oxygen levels can have on butterhead lettuce, basil and arugula grown in deep water culture systems. He set up deep water culture systems with three different levels of dissolved oxygen: 2 ppm, 7.5 ppm and 29 ppm.

“We have been tracking growth and how it affects the morphology of the plants,” he said. “The 2 ppm dissolved oxygen rate is what we were able to achieve without doing any type of aeration. This was our control.”

In another system Baras used a Venturi attachment to a small submersible pump that drew in atmospheric air.

“The highest rate of dissolved oxygen that we could achieve using atmospheric air was a maximum of 8.5 ppm,” he said. “The rate hovers between 7.5 to 8.2 ppm, with it usually averaging 7.5 ppm.”

The third system is a high rate of dissolved oxygen that uses compressed oxygen tanks to deliver 29 ppm.

“This system uses nanobubble technology,” he said. “We were using a prototype device that forces oxygen into a solution in really small bubbles so that the oxygen stays in suspension longer instead of falling out. The lowest rate that we could set was 29 ppm. This level of dissolved oxygen is much higher than what most leafy greens growers are targeting.

“A lot of the flowering crop and cannabis growers who are incorporating dissolved oxygen are actually targeting these higher rates. These growers are achieving 20-40 ppm dissolved oxygen. The flower and cannabis crops tend to prefer to be grown on the dry side. With this type of nanobubble dissolved oxygen technology it opens up this production method to crops beyond leafy greens.”


Some dramatic results

Baras said he has seen some dramatic effects on plant growth with higher dissolved oxygen rates. At the beginning of the trials during the first month the water temperature in the fertilizer tanks was 80ºF. During the second month the water temperature was between 75ºF-80ºF.

“At 2 ppm the arugula plants were severely stunted and were unsalable,” he said. “At this low rate there were also some severe nutrient deficiencies. At 7.5 ppm the arugula looked normal with slight deficiencies. There weren’t any nutrient issues at the 29 ppm rate and the plants almost doubled in size.”

Baras said even at the low rate of 2 ppm some crops could still be marketable.

“The basil and butterhead lettuce could still pass as marketable at the low 2 ppm rate,” he said. “The plants were very small and it would take several more weeks of production to reach the target weights we were aiming for. At the 7.5 ppm dissolved oxygen rate the plants had fairly normal growth as to what we are used to seeing.

For butterhead lettuce at the 2 ppm rate the heads were smaller and compact. The core of the heads were tighter, but actually had a good shape. At the 7.5 ppm and 29 ppm rates, the heads had similar shapes.

Butterhead lettuce (left to right) grown in 29 ppm, 7.5 ppm and 2 ppm of dissolved oxygen.

For the basil there was an increase in height as the dissolved oxygen level increased. Overall the plant height and size increased at higher dissolved oxygen rates.

“At the 29 ppm rate, the plants looked like the plants at the 7.5 ppm rate, but they were about a week ahead,” Baras said. “Both of these rates produced plants with healthy looking morphology, but the plants receiving 29 ppm dissolved oxygen developed faster. On average all of the crops grown with 29 ppm were at least a week faster to finish to a marketable size.”


Differences in root growth

Baras said the roots for the crops in the three rates of dissolved oxygen had different growth patterns.

“The roots in the 2 ppm dissolved oxygen systems were very short and stubby and almost seemed to be retreating from the water,” he said. “The roots remained mostly in the stone wool rooting cubes.”

At the 7.5 ppm dissolved oxygen rate the roots were long and had a lot of lateral branching. Baras said they looked like standard hydroponic roots.

“At the high 29 ppm rate the roots actually had less lateral branching, but they were really white, long and thick,” he said. “But there was less lateral branching. It almost seemed like since there was so much oxygen in the water the plants didn’t need to have as much lateral branching.”


Arugula (left to right) grown in 29 ppm, 7.5 ppm and 2 ppm of dissolved oxygen.

Even though there were differences in the root morphology, there was no significant difference in the root weight for all three dissolved oxygen levels. The average root weight for both the 7.5 ppm and 29 ppm rates was 0.8 ounces. The root weight for the 2 ppm rate was about 0.7 ounces.

For more: Hort Americas, (469) 532-2383;;

David Kuack is a freelance writer in Fort Worth, Texas;

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;;


David Kuack is a freelance writer in Fort Worth, Texas;

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;


David Kuack is a freelance technical writer in Fort Worth, Texas;

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.

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

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.


Hort Americas now distributing Sudlac

Sudlac goes for growth

Sudlac is coming to North America in 2017. The company’s goal is to become the leading manufacturer of shading materials for the global greenhouse horticulture market. This is apparent from the complete restyling of the company brand all the way to the development of its fast-growing team. Behind the scenes, every team member is working hard to build a solid, full-coverage distribution network.

Sudlac’s target group is a large segment in the shading market including growers who choose no-nonsense, reliable, high quality shading products. Sudlac is serving this market with a wide range of products from powder in bags to high tech removable coatings in buckets.

Providing excellent service

Sudlac’s updated approach is practical and service-driven. Last year, the company opened a dedicated sales office in Purmerend, Netherlands, which is close to the international Schiphol Airport and the country’s greenhouse cultivation zone. This enables Sudlac to provide excellent support and service in the Netherlands and worldwide.

“The new office better highlights our presence in the Dutch market,” says Export Manager Jorien Plak-Schouten. “This is the base from which we work and provide support with our sales team. We see worldwide opportunity for our shading products. This is why the Dutch team was reinforced with two new account managers, Ruben Lensing and Michel Seignette.”

A well-trained network of distributors supports product deliveries. There are still opportunities for new distribution partners who want to be part of this positive development.

“Throughout the years, we have gained extensive experience, developing our products such that a distributor can include them in their product selection with full confidence,” says Plak-Schouten.

Sudlac also provides support for product application by utilizing the knowledge and experience of Dutch contract applicators, which can be shared with growers worldwide. These applicators can advise from their practical perspective, sharing the best and most professional application methods with growers.


Fresh new look

Sudlac’s website, packaging, brochures and newsletters are vibrant and informative. The product wizard on the new website assists growers step-by-step in selecting the most appropriate product for the relevant crop, location and greenhouse type. The company’s monthly newsletter highlights interesting information related to products as well as practical experiences.

Sudlac’s new style will be presented officially during various horticultural trade shows in January and February 2017. Trade show visitors can experience the fresh new look and be introduced to the company’s extensive sales team.



Sudlac Eclipse LD

Eclipse® LD is a removable white shading paint for greenhouses. It protects crops against too much light and heat throughout the season and can be applied on the outside of all standard greenhouses. Eclipse LD needs to be mixed with water and can be applied in many situations, making it a basic yet all-round product for horticulture use worldwide. Eclipse LD is highly wear-resistant and easily removed with Topclear at the end of the season.

 – Optimal protection of your crops
 – Adjustable shading intensity
 – Wear-resistant
 – Applicable to all greenhouses
 – Removed with Topclear
 – For all greenhouse surfaces

Why Eclipse LD?
The Eclipse LD shade layer reduces stress and prevents crops and fruits from sunburn, improving production and quality. In countries with a moderate climate, Eclipse LD is mainly used for protecting ornamentals and leaf vegetables in greenhouses. In warmer areas of the world, Eclipse LD is also used for fruit vegetables like tomatoes and sweet peppers.
Eclipse LD is a very efficient and versatile shading agent that reduces the light and temperature in the same ratio. This shading product is flexible in use because you can adjust the number of buckets, amount of spray solution and application method. Eclipse LD is easy to apply and to remove.

Eclipse LD needs to be diluted with water before spraying it onto the greenhouse. Depending on the application method, type of greenhouse and climate, the dilution rate and amount of spray liquid can vary to achieve the best results. Eclipse LD can be applied manually, by machine and by helicopter. See how to use for more detailed information about applications and dosage.

Eclipse LD can be removed with Topclear whenever necessary. Apply Topclear in the advised amount and dilution. Read the complete instructions on how to use Topclear.


Sudlac Transpar

Transpar® is a removable shading agent based on a special pigment that reflects heat radiation very efficiently, while maintaining high photosynthetic light levels. Transpar diffuses incoming light which is beneficial in optimizing the greenhouse climate. It is very wear-resistant and can be applied on the outside of all standard greenhouses. Transpar is easily removed with Topclear at the end of the production season.

 – Minimum light shading, maximum heat shading
 – High diffusion rate
 – Applicable to all types of greenhouses
 – Wear-resistant
 – Removed with Topclear
 – For all greenhouse surfaces

Why Transpar?

High solar radiation means high photosynthetic light levels for photosynthesis. However, it also generates heat radiation which can be stressful to crops. Compared to traditional whitewash coatings, Transpar ensures a higher photosynthetically active radiation (PAR) while the heat radiation (NIR) is partly reflected.

Higher PAR results in more photosynthesis. Photosynthesis is the process where the plant energy from the sunlight transfers into sugars. These sugars are the building blocks for plant growth, fruit production and flower quality.
Heat radiation is not used by the crop for photosynthesis. This radiation heats the greenhouse and the crops leading to plant stress. By reducing the heat radiation in the greenhouse, plant temperature is more moderate, resulting in better quality plants and higher production.

In addition to increased PAR transmission, Transpar has great diffusing properties. This improves the greenhouse climate, resulting in positive effects on the quality and production of the crop.

Transpar needs to be diluted with water before application to the greenhouse. Depending on the application method, type of greenhouse and climate, more or less water and buckets should be used to achieve the best results. Transpar can be applied manually, by machine and by helicopter. See how to use for more detailed information about applications and dosage.

Transpar can be removed with Topclear whenever necessary. Apply Topclear in the advised amount and dilution. Read the complete instructions on how to use Topclear.


Sudlac Optifuse IR

Optifuse® IR is a removable greenhouse coating that scatters the light to a high degree in combination with effective heat protection. Optifuse IR is very wear-resistant and can be applied on the outside of all standard greenhouses. Optifuse IR is easily removed with Topclear at the end of the season.

 -High light transmission
 -High diffusion rate
 -Reduces temperature
 -Improves quality and production
 -Removed with Topclear

Why Optifuse IR?
Optifuse IR offers a very high level of diffusion and a high light transmission in combination with an effective temperature reduction. This combination will ensure more photosynthesis and lower greenhouse temperatures.

The incoming light is scattered by the diffuse coating layer, reaching the leaves from top to bottom and from all sides of the crop. This will improve the photosynthesis and transpiration rates of all plant leaves, resulting in better humidity, temperature and CO2 levels inside the greenhouse. It is proven by research that diffuse light in combination with heat reduction has a positive effect on crop production, quality and growth.

Compared to Optifuse, this Optifuse IR version reflects heat radiation (NIR) very efficiently while maintaining photosynthetically active radiation (PAR) transmission.

PAR is the spectral range of solar radiation from 400 to 700 nanometers that crops use for photosynthesis. NIR is the spectral range of solar radiation from 700 to 2,500 nanometers that is very efficient for generating warmth in the greenhouse. NIR is not used by the crop for photosynthesis.

Optifuse IR needs to be diluted with water before spraying it onto the greenhouse. Depending on the method of application, type of greenhouse and climate, more or less water and buckets should be used to achieve the best result. Optifuse IR is best applied by machine to get an even layer for optimum diffusion. See how to use for more detailed information about applications and dosage.

Optifuse IR is removed with Topclear whenever necessary. Apply Topclear in the advised amount and dilution maximum three days before considerable rainfall.


Sudlac Topclear

Topclear removable coatings cleaner

For removing Eclipse LD, Transpar, Optifuse and Optifuse IR

Topclear is the cleaner used to remove Sudlac coatings Eclipse LD, Transpar, Optifuse and Optifuse IR. By using Topclear, a grower has full control over when the coating is to be removed.

 – Easy to apply
 – Dilute with clean water


Mix Topclear with the necessary amount of clean water. Apply the solution evenly onto a dry greenhouse surface under dry weather conditions and a minimum temperature of 5°C (40°F).
Minimal reaction time is 20 minutes before rinsing with water or brushing. Considerable rainfall will wash away the coating. Only apply Topclear if considerable rainfall is expected in the next few days. Removal of Topclear with roof sprinklers is not recommended.

Could LEDs replace plant growth retardants?

Researchers at Michigan State University used LED lights to produce compact flower and tomato seedling plugs.

By David Kuack
Growers and researchers are studying the effects that specific light wavelengths can have on ornamental and edible crops. Research studies are focusing on the effect light wavelengths can have on a variety of plant processes including growth, flowering, fruiting and postharvest quality.
Michigan State University horticulture professor Erik Runkle and former graduate student, now floriculture/nursery production extension educator Heidi Wollaeger studied the impact the ratio of red to blue light can have on the production of annual bedding plant seedlings. They looked at the effects of red and blue light on impatiens, petunia, salvia and tomato plugs.


Photo 1, DSC_0404, Heidi Wollaeger, Mich. St. Univ.
Michigan State University floriculture/nursery production
extension educator Heidi Wollaeger and horticulture
professor Erik Runkle studied the impact that red and
blue light can have on bedding plant seedlings.
Photos courtesy of Heidi Wollaeger, Mich. St. Univ. Ext.

“These four species are very common bedding plants for U.S. growers,” said Wollaeger. “They are key crops for their sales. The tomato plugs were being grown as vegetable transplants and not for production as greenhouse tomatoes for fruiting.

“We have also used these four species in other lighting trials that we have done recently. We wanted to be able to extrapolate from one study to another. In previous studies we looked at green light and the ratios of blue, green and red light.”
Seed was sown into 128-cell plug trays at a commercial propagator and moved into a large growth chamber at the university within two days where LED and fluorescent light treatments began immediately. The plants were Stage 2 plugs when the light treatments began. The seedlings had cotyledons and no true leaves. They were under the light treatments throughout the entire duration of the study.
Light treatments

The bedding plant plugs were grown in a growth chamber equipped with six individual LED chambers. The plugs grown under fluorescent lamps were grown in a separate growth chamber.


For all light treatments, plants were exposed to 160 micromoles per square meter per second (µmol·m−2·s–1) for 18 hours a day.


Photo 2, DSC_0459, Heidi Wollaeger, Mich. St. Univ.
Plug trays of impatiens, petunia, salvia
and tomato were grown in a large growth
chamber at Michigan State where they
received LED or fluorescent light treatments.

“We chose 10 moles per day because that is a suggested light integral for most plants to be of at least moderate quality,” Wollaeger said.
“We didn’t want to deliver a light intensity much greater because as the intensity increases so does the light installation cost as well as the energy costs to run the lamps. We were implementing a practical light level for growers.”

Wollaeger said the study was terminated after four to five weeks because at that time the plants were ready for a commercial grower to transplant.
“This study simulated what growers would actually do in their facilities if they were to install a sole light source LED chamber,” she said. “They would use this high value propagation space to produce the propagules and then transplant them and put them into the greenhouse. These could be used by growers who are finishing the plants themselves or by a propagator who is selling the plugs to other growers.”
Light effects on bedding plants

Wollaeger said all of the species grown under the red light dominant background with at least 10 µmol·m−2·s–1 of blue light displayed desirable plant growth responses.


“These plants showed compact growth, thicker leaves and thicker stems,” she said. “As a general rule of thumb, growers should provide at least 10 µmol·m−2·s–1 of blue light if they are providing
a red dominant environment to increase plant quality, which results in compact, well-branched growth.
“This treatment might reduce the need for plant growth retardants. If the light environment is being altered to include more blue light in a sole-source environment, stem elongation is reduced. This will depend on the crop. Every crop has a different vigor depending on the species and cultivar. This study only looked at four commercially important species.”


Photo 3, R_B_LEDtomato, Heidi Wollaeger, Mich. St. Univ.
Four bedding plant species, including tomato, grown
under a red light dominant background and under at
least 10 µmol·m−2·s–1 of blue light
displayed desirable plant growth responses, including compact growth,
thicker leaves and thicker stems.

Plants grown under the fluorescent lamps usually produced the most chlorophyll, but also had the thinnest leaves. Impatiens and salvia had greater fresh shoot weight when exposed to treatments without blue light than with at least 80 µmol·m−2·s–1 of blue light.

Impatiens grown under a high proportion of blue light developed more flower buds. Wollaeger said whether this early flowering is a negative or positive effect depends on the plug cell size.
Photo 4, ImpatiensunderallblueLEDlight, Heidi Wollaeger, Mich. St. Univ.
Impatiens grown under a high proportion of blue light
developed more flower buds than
plants provided with mostly red light.
“If the plants are being grown in a small plug size like a 288 cell and will be transplanted into large finished containers, it might not be desirable for early bud development,” she said. “The formation of flower buds could impact the rooting of the plants, but that depends on the cell pack size. If a grower is transplanting the plugs directly into smaller containers, he might want earlier flowering.”
Reduction of tomato intumescences

A benefit of growing tomato plugs under high blue light levels and fluorescent lamps was the reduced incidence of leaf intumescences (sometimes called edema), which are small protrusions that form on leaves, stems and petioles. Wollaeger said this physiological disorder has been associated with a lack of ultraviolet light or blue light.

“This physiological disorder is cultivar specific,” she said. “Some cultivars are more prone to developing this disorder compared to others. ‘Early Girl’ is the cultivar that we used and it did develop intumescences under treatments with small amounts of blue light.”
More greenhouse research

This particular research study did not look at the effects of the light treatments after plants are moved into the greenhouse.
Wollaeger said Dr. Runkle’s lab is currently conducting another study to determine the lasting effect of light treatments on transplanted plugs.

“Whether or not a light treatment has any lasting effect once the propagules are transplanted and placed in the greenhouse is going to depend on the light environment in the finishing location,” she said. “If the daily light integral is at least 10 mol·m−2·d–1 during the plug stage, there is probably going to be some height suppression when the plants are finished in the greenhouse. I wouldn’t expect there would be a major lasting effect of stem elongation suppression once in the greenhouse.”

For more: Heidi
Wollaeger, Michigan State University Extension, Nazareth, MI; (269) 384-8010;;


David Kuack is a freelance technical writer in Fort Worth, Texas;

Kimitec Organic Fertilizers, perfect for Hydroponically Grown Greenhouse Crops

Not alot of time for a post today, but wanted to put a teaser out there that we are looking at an organic fertilizer that should fit well with Hydroponically Grown Greenhouse Greens, Herbs and Veggies.

Email for details or check out our facebook page for images!/pages/Hort-Americas/133476796695370

Hope everyone is having a good summer!

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