Growing Microgreens in Natural Light

And given how little space and infrastructure microgreens need, you can grow them indoors year-round. Dedicate a seed-starting shelf to maintaining your microgreens, and you can sow flats regularly, harvesting them almost constantly. They’re the simplest way to grow fresh greens — even in the dead of winter.

Third, they grow quickly, which means you can produce more. These little greens are ready to harvest in as little as 10 days to two weeks after sowing, so you don’t have to commit your whole summer to tending a vegetable garden. And they’re a great project for young and new gardeners who can reap the rewards with just a little effort and patience.

Getting Started Growing Microgreens in Natural Light

Any shallow container will make a good home for microgreens. Standard 10-by-20-inch open seedling flats are easy to find at nursery supply stores. A clear plastic vented top works as a mini greenhouse, which helps keep your microgreen seeds damp until they germinate.

You can also recycle plastic pint and half-pint containers in which you buy berries or cherry tomatoes. Their vented bottoms offer great drainage, while their clear, vented tops let in light and hold in heat and humidity. Cut the hinge to separate the lids from bottoms first, and place them on a plate or tray.

Most any potting soil intended for seedlings will produce reliable results, as long as it’s free of large clumps, leaves and twigs. You don’t need much. Fill the containers so the soil level is 1/2  to 1 inch below the top of your container, about 1 1/2 inches deep. You can also use a soil-less mix, such as peat, vermiculite or perlite.

You can grow microgreens from any seed. As a rule of thumb, it makes sense to grow each variety separately because they grow at different rates. With that said, you can also experiment with leftover garden seed from last summer.

If you’re dreaming of a microgreen salad, one quick and reliable mix might include radish, arugula, mustard and cress. In a week to 10 days, you’ll be eating flavorful, healthy microgreens with a little kick.

Materials

Although you probably already have everything you need to grow microgreens, here is a list of basic supplies:

• Shallow growing containers, at least 2 inches deep, with vented bottoms. Try 10-by-20-inch seedling flats (without cells), or recycled plastic pint or half-pint containers.
• Clear plastic tops with vents, such as those made specifically for starting seeds — optional but handy.
• Light potting soil for starting seeds.
• High-quality seeds (though a flat of microgreens is a fine way to use up older seeds, given how thickly you can plant them).
• A spray bottle or mister.
• Sharp scissors for harvesting.

Planting

Scatter the seeds over the soil evenly, leaving some room between them. Aim for four to six seeds per square inch — or enough to cover about one-third to one-half of the surface with seeds. Plant a new tray every 10 to 14 days to maintain a ready supply.

Proper Care

You can leave your seeds covered or uncovered to help retain moisture. Some growers cover the seeds very lightly with soil. Eric Franks, co-author of Microgreens: A Guide to Growing Nutrient-Packed Greens, covers his with a thin, moist paper or cloth towel. If you choose to do this, remove the cover once the seeds have germinated. Your other option would be to leave them uncovered and mist frequently.

Water your seeds using a spray bottle to gently mist the soil until the potting mix feels wet to the touch — like a wrung-out sponge. Another easy watering option is to place the growing container in a tray of water and allow the soil to absorb moisture from below — but not so much water as to keep the soil drenched, as Pam Geisel, academic coordinator of the University of California’s Master Gardner program, explains. “Microgreens don’t have a lot of roots, so the soil or mats have to be watered often but not kept soggy wet.” Careful watering once or twice a day is about the only detail that will require attention.

Place the containers in a warm spot where they will receive plenty of natural light. They’re a little more forgiving than traditional seedlings, as they won’t live long enough to become leggy as they stretch toward the light.

Microgreens are so quick to germinate — often in just a few days — that growing them requires little more than watching and watering. Without splashing soil onto your microgreens, a gentle hose, watering can, or mister will be adequate for water needs. Keeping your crop clean means you can eat it right after harvest. This additional Grit.com post gives even more tips for care.

Harvesting

You can harvest your microgreens at any stage, but most hit the plate by the time they have their second set of leaves. They are called their first “true” leaves because they begin to take on a more mature shape and color. You’ll usually notice these after two to four weeks, and they’ll be about 2 inches tall. The longer you wait to harvest them, the more flavor and texture your microgreens will have.

The key to unmarred, clean cuts is to use a sharp pair of scissors. Gently holding onto the tops of a handful of microgreens with one hand, cut the stems with the scissors held in your other hand. It sounds fussy, but it’s not. You’ll get the hang of it. Once harvested, the plants are dead — no leaves will remain. Compost the remaining stems and roots and get ready to start again.

Use the Right Potting Soil to Avoid Disease

Most farmers advise starting over with fresh potting mix for each planting for three main reasons:

• The dying roots and stems from the last crop are decomposing at the same time you are trying to grow your next crop. The decomposition process steals nutrients away from the growing crop, making your greens less likely to thrive.
• Many diseases live in soil. If anything infected your last crop, it will more than likely infect the next one grown in the same soil. “When reusing soils, there can be a problem with damping off and other organisms, such as salmonella,” Geisel says. (Damping off describes fungal ailments that weaken or kill seeds and seedlings.) If the sprouts you harvest show signs of mold or decay, be sure to compost them — do not eat them.
• Your first crop grown in the potting mix theoretically used up some of the nutrients, leaving fewer for the next crop. Franks recommends putting used soil mix in a worm bin. Then, reuse it once the stems break down and the worms have replenished the nutrients.

Store and Enjoy

Delicate microgreens will last longer if you avoid washing them until just before you plan on eating them. Use them liberally to garnish salads, spice up sandwiches, and dress up just about any savory entree. Each mouthful feels like a nourishing treat.

Microgreens are a great way to sneak more nutrients into your diet, and these small wonders can be grown in a flash and just about anywhere you have space for a seedling flat. Give them a try, and before you know it, microgreens will have made their way onto your kitchen table — maybe even year-round.

Varieties of Microgreens to Try

• TASTY: Start with microgreen versions of vegetables you already love. All of them will taste milder than their full-grown counterparts. And it will be easy to distinguish your micro carrot from micro arugula.
• NUTRITIOUS: Brassicas — including cabbage, mustard, kale, broccoli, arugula, chard and radishes — are wildly nutritious and brimming with cancer-fighting phytonutrients.
• POPULAR: Brassicas are the most common microgreen varieties — they’re easy to grow and they produce beautiful colors ranging from deep/silvery green to burgundy. In fact, you can grow microgreens for color as well as taste. Try purple basil or red amaranth — both are gorgeous. Others offer interesting textures, including micro scallions, kohlrabi, chrysanthemum, sorrel, cress, cilantro, carrot, bok choy and fennel.
• EASY: Author of How to Grow Microgreens at Home, Mark Mathew Braunstein says broccoli, radish, beet, cress, lettuce and basil are the easiest to grow, while Johnny’s Selected Seeds says radishes and mustards are two of the fastest-growing options.

Victoria Scanlan Stefanakos lives in Maine and blogs about homestead-related endeavors. Read what Susan grows in her indoor garden in Winter Indoor Herb Garden.