Growing Guide: Microgreens
Microgreens are fun and easy to grow in the classroom and at home. Requiring minimal supplies, space, and effort, microgreens let you and your students witness the miracle of seeds coming alive and growing into a delicious and nutritious snack in just a few weeks.
What are microgreens? They’re edible crops grown in soil and harvested when the plants are a few inches tall. Although leafy greens and herbs are among the most popular plants to grow as microgreens, other options include amaranth, radish, broccoli, sunflower, and even nasturtium!
Microgreens became popular in the 1980s as a gourmet garnish in high-end California restaurants and upscale food markets. Today you can enjoy fresh microgreens in take-out sandwiches and salads, and see them growing on windowsills in homes and schools nationwide.
- Crops that germinate readily and grow quickly are the best candidates for microgreens.
- Microgreens are sometimes called “vegetable confetti,” a playful reference to the tiny leaves in a range of colors. A sprinkling of microgreens brightens any dish.
- Microgreens boast higher levels of nutrients per gram than their mature counterparts. Keep in mind, however, that it takes a very big bowlful of microgreens to equal the weight of a serving of broccoli or cabbage!
- Their short shelf life — as little as a week, depending on packaging, temperature, and other factors — makes them expensive to purchase at the supermarket.
- Growing microgreens in the classroom can pique kids’ interest in eating more vegetables.
- Microgreens have the flavor of the mature plant — you can taste the beet in beet microgreens — and often that flavor is even more intense.
Microgreens vs. Sprouts
Growing your own alfalfa sprouts for salads and mung bean sprouts for stir-fries used to be quite common, but the practice seems to have fallen out of favor in recent years. Sprouts differ from microgreens in that sprouts are grown without soil, and you eat the whole plant, including the root, shoot, and tiny leaves, if any.
Although you can purchase specialized apparatus, sprouts can be grown a glass jar covered with a piece of screen. The process is simple: Soak the seeds in water for several hours or overnight, and then drain the water from the jar, leaving the wet seeds behind. Rinse and drain daily, until the sprouts are ready to eat, usually in a few days to a week. The key to growing sprouts is cleanliness, because the conditions conducive to sprout growth — humidity and warmth — are also favorable to mold and bacterial growth.
Microgreens are a little more forgiving: Because they’re grown in open air, as opposed to the confines of a glass jar, humidity is lower, which all but eliminates the risk of bacteria or mold growth. This may account in part for their surging popularity.
Step-by-Step Instructions for Growing Microgreens
- Decide what to grow. Here are some options: arugula, amaranth, basil, beet, broccoli, buckwheat, cabbage, chard, cilantro, collard, corn, fennel, kale, kohlrabi, mustard, nasturtium, pea, radish, sunflower.
- Choose microgreens seeds. Use seeds specifically labeled for growing as microgreens or sprouts. Seeds that are sold for growing in the garden are sometimes treated with a fungicide to improve germination in cool, wet soil. Organically grown seeds are untreated and therefore are a good option.
- Find containers. Any shallow container will do, even recycled ones, such as foil pie plates and take-out containers. Just be sure they’re clean. You can either poke holes in the bottom and place them on a watertight tray, or plan to water very carefully.
- Add the soil. The best option is a sterile, peat- or coir-based seed-starting mix. Spread a 1” deep layer of pre-moistened planting mix in each container.
- Sow your seeds. Scatter seeds evenly over the planting mix.
- Cover seeds. Spread a thin layer of planting mix over seeds and press lightly to ensure good contact between the mix and the seeds. Misting with water will also help to settle the planting mix around the seeds.
- Place containers in a warm, bright spot. A sunny window is ideal.
- Keep the planting mix moist. If your containers have drainage holes, you can bottom-water by adding water to the tray underneath and letting the planting mix soak up the water. Drain any excess water from the tray. Or you can use a spray bottle to water from above, taking care to thoroughly moisten the soil without over-saturating it — especially important if your containers don’t have drainage holes.
- Observe daily. Check soil moisture and water as needed. Most seeds will germinate in a few days to a week. Look for the tiny, red beet stems and beefy sunflower shoots. Once they’re up they’ll grow quickly. Rotate the containers every day or two so the stems grow straight.
- Harvest your microgreens. Plan to harvest when the plants are 2” to 3” tall, or when they’ve developed one or two sets of true leaves. Use scissors to cut the stems just above the soil.
- Start a fresh batch! Toss the used soil from your first batch into the compost. For best results, start each new batch with fresh planting mix.