Growing Microgreens

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. 

Microgreens are defined by the USDA as edible greens which germinate from the seeds of vegetables and herbs and are harvested without roots at the seedling stage. This product is harvested when cotyledons are fully developed. The cotyledons function within a plant is to supply nutrients to the seedling. The Agricultural Research Service (ARS) researchers tested about 25 varieties of microgreens for their nutrient levels and found on average they had about five times greater levels of vitamins than their mature counterparts.  This is why microgreens are referred to as a superfood product.

Microgreens can be grown at home, inside greenhouses and plant factories. The most common way of production for this product is inside plant factories using vertical farming systems. This system allows you to produce higher yield in less space providing ideal environmental conditions. 

Which are the basic requirements to produce microgreens in vertical farming systems?

Mesh tray

Microgreens can be grown on flat mesh trays. Characteristics we should consider when selecting a tray is good drainage. Bad drainage can trigger fungi development, a very common problem when growing microgreens. Also we should consider irrigation strategies. The most recommended way to irrigate microgreens is using an ebb and flow system, meaning our mesh tray should be able to provide enough surface area to allow the substrate to take up water.

Substrate

Different substrates can be used when growing microgreens. Coconut coir and peat moss are common options. However when thinking about a sale strategy we should consider the best substrate option to improve packaging and shelf life. When microgreens are harvested from the substrate and packaged, shelf life is reduced in comparison to microgreens packaged alive. Substrate mats designed for microgreens production can be a good option to grow microgreens and improve packaging. Substrate mats such as: Biostrate, Vegbed Bamboo and Grodan Cress plate allow you to grow perfect microgreens and transfer your product alive directly to clamshell packaging. Improving product quality (super fresh) and shelf life. 

GrowRack

In order to grow microgreens we need a growing system and to think in a strategy for irrigation. Manual irrigation can be applied in very basic systems. However, the best way to irrigate microgreens will be using an ebb and flow system. In Hort Americas we offer the Hort Americas GrowRack (link to article and/or product) including all the plumbing and pumps required to provide subirrigation to your trays. Distance from each shelf in your GrowRack is also important. We should consider a space to grow microgreens and to provide good airflow over our product. It is recommended to keep at least 1 feet between each shelf.

Lamps

Microgreens require artificial lighting when grown in indoor vertical farming systems. Light requirement for microgreens is low in comparison with other crops. Daily light requirements can go from 8 to 10 mol m2 d-1.  Current by GE, a Daintree Company offers multiple options on lamps and light quality that can be implemented to grow microgreens. Also, research has demonstrated that using specific light quality to grow plants can improve harvest time, texture, color and nutrient content in microgreens in comparison to white LEDs lamps.

Fans

Air flow is very important to maintain good gas exchange in microgreens. Bad airflow can cause an increase in the boundary layer over the surface of the leaf, making it harder for the plant to transpire and take CO2. 

Different aspects should be considered when growing microgreens: seed options, seeding process, germination, irrigation, harvest, packaging, business. The best way to start or improve production is to get the proper training and theory.

You can learn these and more aspects in our next online short course: Microgreens Production (July 24th) Link to register. Microgreens can be a very interesting and profitable option when running a business. In Hort Americas we provide all technical support and products in order to approach all your goals. Come and see all we have to offer!