Microgreens are vegetable greens harvested after the cotyledon leaves have formed at least one pair of true leaves. They are used as a flavor and texture enhancer, as well as a dietary supplement and decorative garnish. Microgreens are immature vegetables, similar to sprouts, but they are not the same.
What Microgreens Growing Mediums Are Available?
Microgreens can be cultivated at your home with some investment in resources. On a small scale, a shallow plastic container with drainage holes, such as a nursery flat or packed salad box, will aid the sprouting and growth of microgreens. Specific trays better suited to sustaining microgreens of a minimum dimension of 10′′ x 20′′ are utilized for commercial-scale growth. There is a variety of materials that can be used to line the trays.
Whatever the medium, it should account for the following:
- A supply of water, air, and nutrients to roots
- Physical support for the plant
- Maximum root growth
The following are some microgreen growing mediums that one can consider:
Soil
A freely and abundantly available medium, the soil is a medium of choice for most farmers. It is all-natural, produces predictable and consistent outcomes, and keeps moisture in the air. The majority of microgreens merely require soil and water to grow. Some vividly colored plants, like radish, may need additional nutrients to thrive.
Avoid peat-based soil to safeguard the microgreen growing environment. Peat is a poor source of nitrogen, which is required by microgreens. Also, peat moss can harbor certain pests, such as mites and nematodes, which hamper the cultivation.
The disadvantages of soil or dirt include the possibility of a mess. Mold can form in the soil, which can cause plant illnesses and root rot. Another disadvantage is that it takes up a lot of storage space because dirt generally arrives in larger containers.
Hemp mats
Hemp mats are an excellent medium composed of braided hemp fiber meant to distribute water equally. Hemp fibers are excellent at retaining moisture, ensuring that the seedlings get the water they need. They are completely compostable and biodegradable. Hemp fiber is a tough, robust fiber similar to coco coir but has a neutral pH. This makes it water retentive and helps in the even distribution of water for the planting.
Hemp mats are pest-free and eco-friendly because they can be composted once the microgreen batch is harvested. When wet, hemp fibers break down in about two weeks, ideal for most microgreen crops. Woven hemp mats absorb water and evenly distribute it throughout the growing tray. This property aids in the rapid germination of seeds and the strong growth of all seedlings. The woven weave also allows for good ventilation, promoting healthy root development.
However, hemp mats have the disadvantage of ripping when wet, making it difficult to remove the mature microgreen crop from the growing tray. To enhance nutrition levels, these mats may require adding a “soluble” fertilizer after planting to boost the level of plant-available nutrients.
Vermiculite
Many people use vermiculite in its natural form for producing microgreens as it is naturally sterile. (It does not support the growth of mold and bacteria.) Because of its neutral pH, vermiculite is an excellent growing medium. Vermiculite gives tiny microgreen roots a good mix of aeration and water, which boosts yield. Further, vermiculite feeds budding plants with nutrients like potassium, magnesium, and other trace minerals.
Vermiculite is a lightweight, easy-to-store, and cost-effective material. If you plan to manufacture batches of microgreens frequently, these properties of vermiculite make it a convenient growing medium. Vermiculite’s nature makes it a better growing medium for bigger seeds such as peas and beans.
On the flipside, vermiculite can appear dry on the surface but be very moist underneath. If you keep adding water to the tray without checking the moisture level towards the bottom, this propensity can lead to rotted roots.
100% natural coconut coir
Between the outside of a coconut and the seed within is a fiber called coir. Coir is a popular choice for growing microgreens because of its incredible capacity to contain water while not killing fragile plants. Coconut coir comes in dehydrated and compressed blocks. This makes it easy to store until you are ready to start a new tray of microgreens or sprouts. Coir is also available in thin, easy-to-handle sheets that you can roll out and cut to fit your growing tray.
Coconut coir has several advantages, including a fine texture that enables adequate aeration and seed growth. Water is equally distributed through the fiber, allowing every seed to be exposed. While coir has a near-neutral pH balance, it doesn’t provide many natural nutrients for your microgreens, and fertilizers need to be added for nutrition.
Hydroponic growing mats
Growing pads can be manufactured entirely of synthetic fiber or natural fiber. Natural fibers such as hemp, coconut, jute, and wood are widely used. As hydroponic mats are sterile, they pose less risk for fungus development or insect infestation than soil. The pads absorb and store water around the microgreen’s seeds/roots, so you don’t have to keep an eye on them all the time. After harvest, the pads are simple to store, reuse, and dispose of.
Microgreens grow more neatly on hydroponic mats. Soils and coconut coir are gritty, and even after washing, some of those particles can end up in your microgreens. Grow mats eliminate this problem by dissolving or cutting neatly away from the plant.
Growing mats have the drawback of requiring you to add fertilizer to your water because they have little to no nutrient content. Also, some of the materials used in growth mats don’t effectively regulate moisture levels around plant roots, which might cause seedlings to weaken or die.
Burlap growing mats
Burlap is made of jute fibers and can serve as a good medium for hydroponics. A good yield of microgreen crop can be cultivated after a lot of trial and error. It is a tedious process to deal with burlap growing pads as you need a continuous flow of water to prevent water clogging.
Bottomline
Growing microgreens at home are not only cost-effective but also an enjoyable hobby. There are many options when it comes to the best microgreens growth medium. Organic potting soil is the best choice for growing microgreens. Other mediums, such as hydroponic matting, hemp fiber, vermiculite, or coconut coir, have unique advantages.
Choose the growing medium that best suits your gardening style and get planting.
References
Basic Facts about Mold and Dampness. (n.d.). https://www.cdc.gov/mold/faqs.htm
Coconut Coir Pros And Cons – Benefits And Drawbacks Of Planting In Coir. (n.d.). Https://Blog.Gardeningknowhow.Com/. Retrieved May 30, 2022, from https://blog.gardeningknowhow.com/gardening-pros-cons/coconut-coir-pros-and-cons/.
J.J. (n.d.). THE BEST GROWING MEDIUM FOR MICROGREENS. Www.Microgreenscorner.Com. Retrieved May 30, 2022, from https://www.microgreenscorner.com/the-best-growing-medium-for-microgreens/
Vermiculite: main uses. (n.d.). BBC Gardeners’ World Magazine. Retrieved May 30, 2022, from https://www.gardenersworld.com/how-to/grow-plants/how-to-use-vermiculite/
THE BEST GROWING MEDIUM FOR MICROGREENS. (2021, September 6). Www.Cocoandcoir.Com. Retrieved May 30, 2022, from https://cocoandcoir.com/blogs/grow-your-own/the-best-growing-medium-for-microgreens/
