A new trend in growing greens for adding flavor to salads, sandwiches, stir-fries, and soups is producing what are called ‘microgreens’.
By Tony A. Rodriguez
These are young edible greens grown from vegetable, herb, or other plant seeds in shallow containers with a sterile potting medium. The seeds used should be those produced in big numbers by open-pollinated vegetables and herbs so as not to incur additional expense in buying seeds.
Microgreens range in size from an inch (2.5 centimeters or cm) to 1.5 inches (3.8 cm) long, including the stem and leaves. A microgreen has a single central stem which is cut just above the soil line when it’s time to harvest the small plants. These have two fully developed cotyledon leaves and usually one pair of very small, partially developed true leaves. Although not as strong in flavor as mature greens and herbs, microgreens can have intense flavors and are very nutritious despite their small size.
Microgreens are older than sprouts and younger and smaller than ‘baby greens’. They’re the smallest of the salad greens and herbs, and can be grown from almost any plant variety that would produce a mature plant, such as arugula, spinach, radish, or basil. Some plants at this seedling stage possess incredible amounts of vitamins and minerals, making them ‘superfoods’, like sprouts. At this intensely energetic stage of plant life, microgreens can also be at their tastiest.
Sprouts, which are seeds germinated by just soaking in water, are eaten whole, with the seed, root, and stem still attached. Microgreens reach a slightly later stage of growth before being harvested by cutting, minus the roots. Only the stalk and leaves are eaten.
Microgreens are a fresh flavor accent in fine dining restaurants, which place a strong emphasis on both the creative presentation and flavor of their dishes. They use microgreens to add a delicate, fresh appearance, color, and texture, combining these with a range of distinct flavors.
For many years in the United States, microgreen growers produced these primarily for sale to upscale restaurants. The tiny plants served as garnish for main dishes like fish or pork to add color and taste. They were also served as mini-salads or were added to a salad of larger leaves such as lettuce or spinach.
Today, microgreens have become widely known and are now used not just by trendy chefs and foodies, but also by anyone who appreciates fresh, tasty food—giving rise to what’s being called the “microgreening of America.” Aside from being among the new culinary buzzwords, microgreens, according to the U.S. National Restaurant Association, are now among the top five food trends in that country.
What Can I Grow as a Microgreen?
You can grow just about any vegetable or herb; many of these seeds are available from the Allied Botanical Corporation (ABC). In producing microgreens, it’s important to use seeds that are plentiful.
As seen in tests carried out at the ABC Research and Development Farm in Tayug, Pangasinan, several of the more suitable varieties to grow and the time it takes for these to germinate and eventually become harvestable are the following:
• Mizuna (Japanese mustard)
• Green Shinkang Pechay
• Tatsoi (Spinach mustard)
• Pak Choi (a variety of Chinese cabbage)
These are fast-growing microgreens; their seeds germinate in two days after sowing (DAS) and the seedlings are harvestable as microgreens in five to 10 DAS. Except for radish, all are brassicas (of the genus Brassica in the Mustard family Brassicaceae), which are packed with vitamins, minerals, and phytonutrients, and are among the most healthfully beneficial vegetables that people can eat.
Medium-fast growers are arugula, green amaranth, red amaranth, and basil. The seeds of these germinate in four DAS and take seven to 12 DAS to harvest as microgreens. The amaranths here are of the leaf species locally known as ‘kulitis’. “Slow” growers whose seeds germinate in five DAS are beets, chives, coriander (wansoy), and dill. The seedlings of these take 10 to 15 DAS to harvest.
Growing microgreens for your own kitchen is much better and cheaper than buying them—if there are any growers who sell them in the first place. In fact, you can make arrangements with a restaurant or any food outlet and start a profitable microgreen production business at home. Microgreens are a novelty crop that can be easy to promote at your local farmer’s market.
Try growing different herb-veggie mixes for a blend of tastes and colors, adding the varieties your customers like. Microgreens are simple and easy to grow, provide quick harvests for not much work, and are a perfect crop for even inexperienced urban farmers who don’t have spacious gardens. Unlike most other specialty food crops, microgreens can be ready to sell in just 10 to 20 days. As it allows for more control over light and temperature, indoor growing is preferable for small growers, who can grow their crops more quickly and make their harvests more predictable.
How to Grow Microgreens
You can grow microgreens in containers outdoors or indoors in a spot where they will get at least four hours of sunlight, such as a sunny windowsill facing south. A small and simply-built rain-sheltered nursery will also be fine.
It’s best to plant micogreens in clear or opaque plastic containers with drainage holes. Choose one that’s at least five cm deep, 30 cm wide, and 45 cm long. Fill it with a good-quality growing medium, such as Klasmann Peat-based Substrate, and smoothen the material. Scatter the seeds so they’re about 1/8 to 1/4 inch apart, and cover with 1/8 inch of substrate.
Cut a piece of cardboard to fit inside the container. Gently press the cardboard onto the substrate to create a flat, even surface, lightly pressing the seeds into it.
Water gently but thoroughly with hand-held sprayers. Do not let the substrate dry out, and prevent it from becoming waterlogged by pouring off excess water that collects in the drip tray after watering. Be sure to remove weeds so that the tiny greens don’t have to compete with them for water and nutrients.
You can grow a single vegetable or herb crop in a container or plant a blend of those whose seeds germinate at the same time to provide a colorful variety, such as, with green and red Amaranth or two species of Mustard.
Since you’ll be harvesting the greens so young, you don’t need to fertilize them while they’re growing with Klasmann Substrate. Microgreens also grow for such a short period of time so pests and diseases are rarely a problem.
The best time to harvest microgreens is when they’ve developed their first set of true leaves. The first ones to grow are seed leaves and aren’t at all like the actual leaves of the plant, which generally develop about 10 days to two weeks after planting. To harvest, simply snip the microgreens just above soil level. Cut them at the base with a sharp knife. Don’t use scissors because these will pinch the stalks.
It’s best to harvest right before delivering to customers because microgreens are delicate and wilt easily, although they can last for a few days if properly refrigerated. Pack your harvested microgreens in single-serve flexible plastic salad containers with hinged covers.
You won’t be able to get more than a harvest from one planting of microgreens. As the plants haven’t had much time to develop, and you snip off everything, these have no way of generating new growth. You’ll need to plant another crop after harvest by simply sowing fresh seeds and covering these with substrate. No need to remove the old roots as these are good sources of organic matter. There’s also no need to replace the growing medium; it is good for several more microgreen crops.
This appeared in Agriculture Monthly’s June 2015 issue.