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How to Grow Microgreens: A Beginner Guide
Written by David S.
To grow microgreens, scatter seeds densely over a thin layer of moist potting mix in a shallow tray with drainage, keep them warm and evenly moist until they sprout, then move them into bright light and snip the shoots with scissors about one to three weeks later, once the seed leaves are up and the first true leaves appear. They need no fertilizer, and easy starter varieties include radish, broccoli, pea, and sunflower. One important note: microgreens are not the same as sprouts, and they are grown and eaten differently.
Quick answer: Fill a shallow tray (with drainage) with a thin, moist layer of soilless mix, sow the seeds thickly and evenly, and cover lightly. Keep it warm and damp (not soggy) until the seeds sprout, then give bright light in a sunny window or under a grow light. Harvest in about one to three weeks by cutting the shoots just above the soil once the first true leaves show. No fertilizer is needed. Start with radish, broccoli, pea, or sunflower, and never grow tomato, pepper, eggplant, or potato as microgreens, since their seedlings are toxic. Microgreens are not sprouts: they are grown in a medium with light and cut above the soil, which makes them lower-risk to grow than water-grown sprouts.
| Microgreen | Flavor and notes | Typical time to harvest |
|---|---|---|
| Radish | Peppery, fast, very forgiving | About 7 to 10 days |
| Broccoli and other brassicas | Mild, the fastest group | About 7 to 10 days |
| Pea | Sweet, tender shoots | About 10 to 14 days |
| Sunflower | Nutty and crunchy | About 8 to 12 days |
| Beet and chard | Colorful stems, a bit slower | About 2 to 3 weeks |
| Basil and cilantro | Aromatic herbs, patience crops | About 2 to 3 weeks |
What Are Microgreens (and How They Differ From Sprouts)
Microgreens are young, tender edible greens grown from vegetable and herb seeds and harvested once the seed leaves (cotyledons) have opened and the first true leaves are just emerging; you cut the shoot off at the base, right above the growing medium, and leave the roots and spent seed behind.[1] That happens fast: most are ready about one to three weeks after sowing, when they are still only about 1.5 to 3 inches tall.[2]
It is worth clearing up a common mix-up: microgreens are not sprouts. Sprouts are germinated seeds grown in water, usually in the dark, and eaten whole, seed and root and all. Microgreens are grown in a medium with light and harvested by cutting the shoot above the soil.[1] That difference matters for safety: the potential for bacterial growth is much lower in microgreens than in sprouts,[3] partly because microgreens are grown in a medium and exposed to light, which helps keep the pathogen risk below that of warm, wet, water-grown sprouts.[4]
How to Grow Microgreens Step by Step
Start with a shallow tray or container that has drainage holes, and fill it with a thin layer of a well-draining soilless mix moistened to the feel of a wrung-out sponge.[5][6] Scatter the seeds generously and evenly across the whole surface and cover them very lightly.[5]
Keep the tray evenly moist but never soggy. Misting the surface or watering from the bottom works well, and bottom-watering has the advantage of keeping the leaves and stems dry.[2] Many growers cover the tray to keep it warm and dark for the first few days while the seeds germinate, then uncover it.[6] Once the seedlings are up, give them bright light: a south-facing or west-facing window is ideal, and an east window works with at least four hours of sun, or use a grow light for roughly 16 to 18 hours a day.[5] When the first true leaves appear, harvest by snipping a cluster with clean scissors just above the soil line; most microgreens are a single harvest, since the cut roots will not regrow.[5]
The Best Microgreens to Grow
For fast, forgiving results, the brassicas are the easiest group and have the shortest cycle, often ready in little more than a week: broccoli, radish, cabbage, kale, mustard, arugula, and kohlrabi.[1] Pea and sunflower are also easy and satisfying, while beet and chard add color and aromatic herbs like basil and cilantro are rewarding but slower, so treat those as patience crops.[6]
There is one group to avoid entirely: do not grow tomato, pepper, eggplant, or potato as microgreens. These nightshade-family plants are not edible at the seedling stage, because they contain alkaloids that are toxic to people at high levels.[1] For the same reason, skip seed saved from wild or unidentified plants, and avoid pesticide-treated seed, since for some crops the seed coat stays on the seedling you eat.[2]
Care and Common Problems
Microgreens are refreshingly low-maintenance. They need no fertilizer, because the short growing cycle runs on the food stored in the seed itself.[5] The main thing that goes wrong is mold or damping-off, which is favored by warm, humid, stagnant conditions. Good airflow is the best prevention, so run a gentle fan or crack a window, and water from the bottom so the foliage stays dry.[6][2] A fuzzy white film at the soil line is sometimes just harmless fine root hairs rather than mold, but if growth looks grey or musty, improve the airflow, sow a little less densely, and keep the surface drier.
Finally, a few simple food-safety habits. Use clean trays and clean water, cut with a clean knife or scissors, and rinse the microgreens in fresh drinking water before you eat them.[2][4] For more homegrown greens, see our guide to growing leafy greens and our picks for the fastest-growing vegetables, and if you are curious how microgreens compare to their water-grown cousins, our overview of sprouts and microgreens.
Microgreens FAQ
How do you grow microgreens?
Sow seeds densely over a thin layer of moist soilless mix in a shallow tray with drainage, cover lightly, and keep it warm and evenly moist until the seeds sprout. Then move it into bright light, and harvest in about one to three weeks by cutting the shoots just above the soil once the first true leaves appear.[5]
What is the difference between microgreens and sprouts?
Sprouts are germinated seeds grown in water, usually in the dark, and eaten whole, seed and root included. Microgreens are grown in a medium with light and harvested by cutting the shoot above the soil. Microgreens also carry a lower food-safety risk than sprouts.[1]
What are the best microgreens to grow?
For beginners, the brassicas are fastest and most forgiving, including broccoli, radish, kale, and mustard, along with pea and sunflower. Basil and cilantro are rewarding but slower. Never grow tomato, pepper, eggplant, or potato as microgreens, because their seedlings are toxic.[1]
How long do microgreens take to grow?
Most microgreens are ready about one to three weeks (roughly 7 to 21 days) after sowing, harvested while they are only about 1.5 to 3 inches tall, once the first true leaves start to show. Brassicas like broccoli and radish are among the fastest.[2]
Why is my microgreen tray growing mold?
Usually too much moisture and too little airflow, which invites mold and damping-off. Water from the bottom to keep the leaves dry, run a gentle fan or open a window, and sow a bit less densely. Note that a light fuzz at the soil line can be harmless root hairs rather than mold.[2]
Sources
- [1] Penn State Extension, The ABCs of Microgreens: extension.psu.edu
- [2] Penn State Extension, Growing Microgreens: extension.psu.edu
- [3] UConn Extension, The Amazing Power of Microgreens: extension.uconn.edu
- [4] Penn State Extension, Ensuring Food Safety in Microgreens Production: extension.psu.edu
- [5] UC ANR Master Gardeners, It Is Easy to Grow Microgreens Indoors: ucanr.edu
- [6] Utah State University Extension, Grow Your Own Microgreens: extension.usu.edu
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