Microgreens can be a great option when selecting a product to start a business with, or to expand your current market. Why? Microgreens are relatively easy to grow in comparison to other crops, and cycles are very short. Therefore, you can quickly learn and improve your production technique, correct mistakes and become a good producer.
Microgreens are gaining attention from small, medium and large growers. This is a product that can be used to expand a current market or start a small business with good profits.
While Grodan rockwool may be more often associated with greenhouse tomatoes and cucumbers, controlled environment growers are quickly learning that this substrate is an ideal choice for specialty crop production.
Hort Americas partnering with VegBed to offer their sustainable bamboo fiber microgreen mats
Press Release – NEW YORK, NY [February 12, 2019] – Hort Americas, North America’s top commercial horticultural supplier, and VegBed, the leader of innovative hydroponic growing mediums have announced today an exciting new partnership to offer microgreen farms a sustainable medium to grow with.
The LED light recipes that NASA scientists are developing on Earth could eventually be used by astronauts in space and growers on the ground to optimize the production of food crops.
National Aeronautics and Space Administration (NASA) has been growing plants in space for research since the early 1980s. Within the last five years, NASA has been focusing on growing plants in space primarily for food production and as an astronaut life support system.
When choosing horticultural lighting, growers need to consider lighting efficiency and how the lighting will be used.
There is a big difference between lighting efficiency for horticulture and lighting efficiency for consumer use. The difference is in who is receiving the light.
Urban grower Karla Garcia is proud to announce the creation of her new company, Microgreens FLN based in Sonora, Mexico. Karla is a recent graduate with honors and a master’s degree in plant science from the University of Arizona. She is proud of her company’s commitment specializing in microgreens production using an indoor vertical farming strategy. Microgreens are an emerging class of specialty leafy greens and herbs. The crops are harvested when the cotyledons are fully developed and in some cases when the young plants have one true leaf.
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.
CROPS: Local by Atta produces a variety of lettuces, basil, kale, Swiss chard, bok choy, cilantro and microgreens. Products are sold at farmers markets, health food stores, grocery stores, restaurants and through a weekly basket program. The basket program is expected to increase sales as the company looks to expand with pick up at local businesses, municipal buildings and its new production facility.
Grodan stone wool products offer the benefits of high irrigation efficiency, plant steerability and uniform crop development.
Grodan stone wool substrates are made from basalt rock that is processed at a very high temperature (over 2,900ºF). This hygienic, inert substrate offers vegetable and ornamental plant growers the opportunity to control growth from propagation to harvest.
“Grodan stone wool products are inert,” said Rens Muusers, Grodan Technical Sales Manager for the USA. “This means the grower has full control over what is happening in the substrate. Being inert, Grodan stone wool doesn’t bind nutrients and chemicals like other substrate types may do. Any fertilizers, pesticides or other chemicals, including growth regulators, that are applied to the stone wool are available to plants.
Linked to stone wool’s inert nature, Muusers stated growers have more opportunities to steer their crops.
“Other substrates that aren’t inert may bind elements, pesticides or other chemicals that are applied to enhance plant growth or health,” he said. “This may result in having to apply more of a chemical in order to have the same efficacy. The amount of chemical that will need to be applied to stone wool will be lower and it will be more effective than in non-inert substrates. This also helps growers to minimize their input costs.
“Using methods to control water content and EC (electrical conductivity) levels within the substrate allows growers to influence plant growth.”
Muusers stated by controlling the water content and EC in the stone wool, growers can influence the plant balance between vegetative and generative development.
“The steerability offered by Grodan products can result in earlier production, improved plant, fruit and flower quality and improved plant health,” he said. “All of these benefits result in better resilience to insect pests and disease pathogens.
“Also, stone wool can have a buffering impact on the pH in the nutrient solution, slightly increasing pH in the substrate. This increase is minimal compared to the impact of plant and microbial activity in the root zone on pH.”
Muusers indicated another benefit of using stone wool is crop uniformity.
“Because Grodan stone wool products are manufactured in state-of-the-art facilities with strict standards and quality controls, it is a very uniform substrate,” he said. “Depending on the Grodan product being used, this allows growers to produce very uniform crops. The uniformity of seedlings produced in stone wool plugs results in faster germination and quick crop establishment.
Grodan AO plugs and Grodan AX plugs
Grodan AO and AX stone wool plugs are ideal for starting many crops. The plugs are available in sheets that fit into 1020 trays. AO plugs are connected to each other at the top of the plugs. AX plugs are attached to each other at the bottom of the plugs. Muusers said there are also some options in regards to the seeding hole size as well as with the dimensions of the plugs.
“The properties of the AO plugs are exactly the same as the properties of the AX,” he said. “The only difference is where the plugs are attached to each other.
Grodan AX 25/40 cube with lettuce roots and stem post-harvest.
“AO plugs are ideal for NFT systems with smooth gutter surfaces and also for deep flow systems. Some NFT systems use gutters with grooves on the surface for which growers may prefer the wider base and greater bottom surface area of the AX plugs which may be more stable in these systems.”
Muusers said both plugs are used mainly for leafy greens and culinary herb production. There are also growers who are using them for aquatic plants.
Grodan Cress Plate
The Cress Plate is a fairly new product used primarily for the production of microgreens. It is the thinnest product of Grodan. It is only 1 cm thick, less than ½ inch.
Cress Plates come in two sizes. One size fits into 1020 trays. A larger size is used by some growers who need customized sizes. Growers are able to cut the Cress Plate sheet to the exact size they need.
“The Cress Plate has the same beneficial characteristics as other Grodan products,” Muusers said. “It’s inert, clean and hygienic. It’s a uniform product. It holds water evenly. The Cress Plate also provides quick, easy germination and even development of a microgreen crop.”
Muusers indicated growers use Cress Plates in a couple of ways.
“Some growers sell the microgreens with the Cress Plate, essentially selling a living product,” he said. “This allows the end consumer to use the freshest product longer, something that is valued by customers like restaurants. “Growers who produce baby greens and baby lettuce tend to harvest off of the Cress Plates. By harvesting higher up the plants, the plants continue to grow and produce for several harvests. This multiple harvest method is preferred to the uncommon practice of reusing substrates.”
Muusers stated reusing the Cress Plates is risky, just like reusing any substrate.
“There is the possibility of sterilizing the used substrate with steam or some other technique,” he said. “When a sterilizing technique like steam is used, it can have a negative impact on the properties of the substrate. I wouldn’t recommend harvesting and then resowing on top of a previously used Cress Plate because of the risk with potential disease issues and the potential negative impact on germination and growth.”
Grodan Delta Blocks
Grodan blocks come in different sizes and are ideal for both ornamental and vegetable crops.
“Depending on the crop, once a seedling is germinated in a plug it can be transferred into a block and then transplanted into a finish substrate to be grown on,” Muusers said. “Tomatoes and peppers are usually propagated in plugs and then transplanted into blocks. The final grower purchases the young plants in blocks and transplants them into the final substrate such as Grodan slabs. For cucumbers, which are a relatively quick crop, those are sometimes sown directly into blocks, instead of plugs.”
There are different size blocks for different size crops. A standard block size is 10 cm-by-10 cm-by-6.5 cm, which is referred to as a 4-inch block.
Muusers indicated that some growers put multiple plants into one block depending on the crop.
“For tomatoes, growers are looking for a certain head density per square meter,” he said. “The head density per square meter is sometimes achieved by growing multiple plants or by pinching the plants. Tomatoes are the primary crop that growers plant more than one seedling in a block.”
Muusers stated this method of planting multiple plants is also done with cucumbers and peppers. Another reason a grower sows multiple plants into blocks is to try to save on the cost of the blocks.“Some growers use 6-inch blocks instead of 4-inch blocks and put two plants in them,” he said. “In my opinion, it is always better to put one plant in one block. There is less competition resulting in better seedling uniformity as well as a more uniform crop.”
The blocks, like the plugs, are inert and are steerable. Muusers stated the blocks are also important in regards to irrigation efficiency—how the water content and more particularly, the EC, are refreshed within the substrate.
“Grodan focuses on good root growth and uniform root growth throughout the blocks,” he said. “Also, the blocks need to be able to withstand the rigors of handling during propagation. Their structure must remain stable throughout the growing process to be able to support the plants especially when the blocks are moved around. The blocks won’t break or fall apart.”
Grodan Gro-Slabs
Muusers indicated that Grodan slabs come in different product types developed to meet the challenges and needs of different crops.
“We have different slab types for different applications,” he said. “The slabs differ in fiber orientation and fiber thickness to deliver the kind of functionality a grower is looking for. The Grodan plugs and blocks have the same fiber orientation. They are designed for quick root establishment.”
There are Grodan slabs designed for vegetable crops. These crops are usually short term, less than one year. There are slabs designed for longer horticultural ornamental crops that are grown for longer than a year. The slabs for long term crops, including cut roses and gerbera, have a stronger fiber structure to withstand the longer production period.
“Grodan slabs are very uniform,” Muusers said. “Since the substrate is inert, they offer a high degree of crop steerability. This offers a lot of options for irrigation strategies combined with the substrate to influence plant development in a vegetative or generative way.”
David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.
Dean Kopsell, University of Tennessee
Eating marigold petals
Dr. Dean Kopsell talks about why we should eat marigold petals and what his students found to be the best red to blue ratio for peak carotenoid concentrations.
Dean is a professor at the University of Tennessee and has studied an eclectic range of crops including Arabidopsis, basil, broccoli, cilantro, kale, lettuce, microgreens, onions, purslane, spinach, squash, turfgrass, and tomatoes.
1. Dean’s UT url:
http://plantsciences.utk.edu/kopsell.htm
2. Selected work of Dean Kopsell:
https://works.bepress.com/dean_kopsell/
3. Dean’s Social Media:
Dean on Twitter: @UTPhytonut
2015 ASHS Undergrad. Educator Award winner Dr. David Kopsell pictured with his older, less talented brother. pic.twitter.com/6Wad96QAVs