What are Microgreens?
Trendy microgreens are a simple solution to getting more vegetables on your plate this winter. Five-star chefs call them “vegetable confetti” and sprinkle them liberally on salads, sandwiches, and plates. They provide color, crunch, and diverse taste. Available year round, hipster grocers and farmers markets sell them at $30 to $50 a pound. But they are so easy to grow at home, they should become a regular part of your healthy lifestyle.
Microgreens are like a cross between a sprout and a baby leaf lettuce. Unlike sprouts, microgreens are grown in soil. They are harvested as soon as the first two or four true leaves appear. Unlike baby leaf lettuce, you only get one harvest from these greens. But like sprouts and baby greens they are a powerhouse of nutrition.
Microgreens allow you to produce a lot of fresh greens for salad, stir fries, and soup in a short time. Many varieties of flavors are possible from spicy mustard and radish, to juicy sunflowers, or sweet pea shoots.
Your windowsill salad can be ready in as little as 2-3 weeks! They are harvested only once, by cutting the plant at the soil surface. The roots remain in the pot. Then the pot is replanted for another crop in the same soil.
How to plant microgreens
- Use a shallow pot or container that is at least 2″ deep, with good drainage.
- Fill the container with sterilized potting soil to ½ inch from the top. Microgreens don’t need additional fertility. Most of the energy that they need for growth is inherent in the seed.
- Sprinkle your seeds for microgreens liberally on the soil surface. Microgreens are broadcast densely. Cover loosely with a light layer of additional soil.
- Firm the soil in place.
- Sprinkle the surface of the soil with powdered cinnamon to prevent damping-off disease. You can use older spices for this.
- Water the pot from below, rather than watering with a watering can. Do this by letting it sit in a pan of lukewarm water until the surface of the pot is lightly damp. Then drain the planting container until it doesn’t drip any more.
- Place the container on a tray to catch the drips and protect your carpets and furniture.
- Provide adequate light for growth. Without strong light microgreens will grow spindly and leggy. Microgreens can be grown in a sunny window if you live where there is adequate sunlight year round. If you live north of the 40th parallel, you’ll need supplemental light in the winter months to grow microgreens.
Lights and water
Use a full spectrum grow light, if necessary to allow for adequate growth. The light should be placed 4 inches above the top of the leaves. This is the set up I use in Canada to grow microgreens in winter. The light can be easily raised or lowered as necessary.
- Keep the soil moist. Microgreens are shallowly rooted and require more frequent watering than plants like lettuce, which roots more deeply. If the soil surface is dry you’ll need to water.
- Mist the soil surface and the emerging plants if you live in an area with low humidity. Microgreens grow quickly, and need higher humidity than seedlings.
How to harvest microgreens
When the seeds germinate and the plant emerges from the soil, the seed leaves (cotyledon) unfurl first. A few days to a week later, the first true leaves emerge. Once the first set of two or four true leaves are fully open your microgreens are ready to harvest. Your microgreens will be 1½ to 2 inches tall. Sunflower microgreens or pea microgreens may be little taller at 3-4″ high at harvest time. Cut them off at the soil surface with scissors.
How to serve microgreens
Wash the greens under cold water and drain well. You can use them on sandwiches as you would sprouts to add color and crunch, add them to smoothies for extra nutrition, or sprinkle them on stir fries or soup, just before serving.
Larger microgreens like sunflowers or pea shoots work well in salads. Smaller microgreens like kale, amaranth, chard, and pac choi, work better as an addition to sandwiches or wraps, as you would use sprouts. Use them as a garnish. Sprinkle them on hummus or spinach dip. There are so many ways to use them.
Avoid using larger beans, like kidney beans, as microgreens. The leaves of some beans are toxic and shouldn’t be eaten.
A perpetual harvest at home
My microgreen set up has four shallow planting containers. I could plant all four at once and have a single large harvest two to three weeks from planting. If I planted again, I’d be waiting another 2 or 3 weeks before I could harvest again. It would be a cycle of feast, then famine.
By planting one of the four trays every five days and replanting as I harvest, I can maintain a small supply of microgreens perpetually, with the same amount of effort, and the same cost in energy.
The first tray planted would be harvested 14 to 18 days after planting. Each subsequent tray would be harvested 5 to 7 days after the last tray that was harvested, and replanted with fresh seed. After the first 2 weeks you’d have a fresh harvest of microgreens every week.
You will need to replenish the soil with fresh, sterilized potting soil after 2 or 3 rounds of microgreens. This will keep the fungus that causes damping off disease from getting the upper hand.
Where to find seeds
Microgreens are becoming more common in seed catalogs. The seeds sold as microgreens are generally inexpensive, open pollinated varieties of regular vegetables, sold in larger packages and labeled microgreens. Only a few varieties, such as Abundance Kale and Roji Leaf Radish, are selected specifically for microgreen production. Check your favorite seed company for their selection of microgreens, but feel free to also browse through their regular vegetable selections for likely microgreen candidates.
Choose organic seed rather than conventionally grown seed and keep your family safe from pesticide and herbicide residues.
Some seed suppliers sell seed mixtures in a single package. If you are brand new to gardening, this option gives you a variety of flavors and textures in one planting. The seeds in these packages mature at the same time, so they can be harvested together. The seed catalog will give you the “days to maturity”, usually 14 or 21 days.
If you have a lot of older seed packages that you plan to replace with fresh seed this year, consider using them. Since microgreens are planted densely, a lower germination rate is acceptable.
Lettuce is not generally used as a microgreen because of the highly perishable nature of lettuce. If you’d like to grow lettuce indoors, the technique is slightly different, than growing microgreens. See the directions here.
Common vegetables used as microgreens
- Abundance Kale
- Bulls Blood Beets
- Dwarf grey sugar peas
- Lemon grass
- Magenta Sunset Swiss Chard
- Pac choi
- Roji Leaf Radish
- Russian Kale
- Shiso (Red perilla)
- Popcorn [how to grow]
Try growing these colorful greens this winter. If you plan it right, you can have a perpetual harvest of nutritious greens right up till the first lettuce is ready in your outdoor garden. And here’s a bonus: if you live in an apartment and don’t have access to an outdoor garden space, microgreens provide nutrition, taste, and variety year round.