Microgreens are the fastest crop you can grow: tiny vegetable and herb seedlings, cut 1–3 weeks after sowing, that pack intense flavor and color into a few inches of growth. You need no garden, just a shallow tray, a bag of potting mix, seed and a window or grow light. This guide explains how to grow microgreens step by step, which crops are easiest, how much seed to use, the blackout trick that gives longer stems, and how to harvest and store them, with figures from university extension trials.
Microgreens at a glance
| Step | What to do |
|---|---|
| Container | Shallow tray with drainage holes; a 10 × 20 inch “1020” flat is standard |
| Medium | 1–1½ inches of moist, soilless potting mix or coconut coir (not garden soil); no fertilizer needed |
| Seed | Untreated seed, about 10–15 g (1 tablespoon) of small seed per 1020 tray |
| Soak? | Large seeds only (pea, sunflower, beet, chard, cilantro, buckwheat): 6–12 hours |
| Germination | Covered and dark, about 70–75°F, for 1–4 days (longer for slow crops) |
| Light | About 16 hours a day under grow lights 6–12 inches above the plants, or a bright window |
| Water | Mist at first, then water from below; moist but never soggy |
| Harvest | 7–21 days after sowing, when 2–3 inches tall and the first true leaves appear |
| Storage | Refrigerated, about 10–14 days |
Microgreens vs sprouts vs baby greens
| Sprouts | Microgreens | Baby greens | |
|---|---|---|---|
| How grown | Germinated seeds in water, usually in a jar | Grown in a medium, with light | Grown in a medium, with light |
| What you eat | Whole seed, root and shoot | Stem and leaves, cut above the soil | Young leaves |
| Size and age | A few days old | 2–3 inches, 7–21 days | 4–6 inches, 21–40 days |
| Regrows after cutting? | No | No | Yes, 1–2 more cuts |
The microgreen and baby green stages are as defined by University of Maryland Extension. Because microgreens are grown in light and cut above the medium, they avoid the warm, wet jar conditions that make raw sprouts a recognized food-safety risk.
Best microgreens for beginners
Cabbage-family crops (radish, broccoli, kale, mustard, arugula) germinate fast and are the easiest place to start. This table combines crop timings from Utah State University Extension trials in standard 1020 trays:
| Crop | Seed per 1020 tray | Soak first? | Days covered (dark) | Days to harvest | Flavor |
|---|---|---|---|---|---|
| Arugula | 10 g | No | 1–2 | 6–8 | Peppery |
| Radish | 42 g | No | 1–2 | 8–12 | Spicy, crunchy |
| Broccoli | 28 g | No | 2–4 | 8–12 | Mild cabbage |
| Kale | 28 g | No | 1–2 | 8–12 | Mild, sweet |
| Pea shoots | 150 g | 6 hours | 3 | 8–10 | Fresh pea |
| Sunflower | 48 g | 12 hours | 3 | 9–10 | Nutty |
| Mesclun mix | 28 g | No | 3–5 | 12–14 | Varied |
| Basil | 28 g | No | 4–7 | 12–16 | Aromatic |
| Cilantro | 28 g | No* | 7–14 | 21–28 | Citrusy |
*Maryland Extension lists cilantro among seeds that benefit from a 6–12 hour soak, along with beet, Swiss chard, buckwheat, chickpea and mung bean. Utah State’s figures are for denser commercial-style sowing; Maryland and Penn State recommend about 10–15 g (roughly 1 tablespoon) of small seed per tray for home growing. Don’t mix species in one tray, as they grow at different speeds.
What you need
- Trays: any shallow container with drainage holes, such as a clean plastic food container. Commercial setups use two nested 10 × 20 inch trays: one with holes for the medium and one without to hold water underneath.
- Growing medium: a lightweight soilless potting mix or coconut coir (adding a little vermiculite helps hold moisture). Maryland Extension notes garden soil is too dense, and fertilizer isn’t needed because the seed supplies what the seedlings use before harvest. Hydroponic mats (hemp, coir, jute) also work.
- Seed: buy untreated (or organic) seed. Penn State warns against pesticide-treated seed, because the seed coat can stay on the seedling and be eaten. Bulk packs are far cheaper per tray than small garden packets.
- Light: a bright window can work, but a simple LED grow light gives better, sturdier results, especially in winter. See our LED grow light review.
- Spray bottle, scissors and a timer.
How to grow microgreens step by step
- Soak large seeds if needed. Pea, sunflower, beet, chard and cilantro germinate better after 6–12 hours in water.
- Fill the tray. Add 1–1½ inches of pre-moistened potting mix or coir. It should feel like a wrung-out sponge. Level and lightly firm the surface.
- Sow thickly and evenly. Scatter the seed so seeds sit about 3/16–1/4 inch apart, then press them gently into the surface. Microgreens are not thinned.
- Cover and keep dark. Mist, then cover with another tray or a lid to hold moisture and warmth. Utah State places a 2–5 pound weight on top for the first half of the covered period, which helps roots anchor. Keep at about 70–75°F; cabbage-family seeds sprout in about 36 hours at 72°F.
- Keep them in the dark a little longer. Once roots are visibly anchored, raise the cover so it no longer touches the seedlings and keep them dark for another day or two. Stems stretch, which makes cutting easier.
- Give them light. Uncover and move them into strong light: about 16 hours a day with lights 6–12 inches above the plants, on a timer. Lettuce, arugula, mustards and Asian greens tolerate lower light.
- Water from below. Mist for the first few days, then set the tray in water or add water to the bottom tray so leaves stay dry. Keep the medium moist, never waterlogged, and empty any standing water.
- Keep air moving. A small fan on a gentle setting helps prevent mold and damping-off.
- Harvest. When most plants are 2–3 inches tall and the first true leaves are appearing, usually 7–21 days after sowing.
How to harvest and store microgreens
- Cut the stems just above the medium with clean, sharp scissors or a knife, leaving the roots behind.
- Microgreens do not regrow after cutting. Compost the roots and medium, or screen it and mix it 50:50 with fresh mix for the next tray; Penn State notes fresh medium each time limits disease.
- For storage, Penn State found that keeping microgreens at 41°F in the dark extends shelf life to 10–14 days, compared with 2–4 days at room temperature. Dry them well first: excess moisture and condensation shorten storage.
- Rinse just before eating rather than before storing.
How much will you get? Maryland Extension reports that 1 tablespoon of arugula seed in a 10 × 20 inch tray yields about 8–12 cups of microgreens. Penn State measured an average of about 0.3 lb (136 g) per tray, from 0.1 lb for cilantro to 0.44 lb for red mustard.
Common problems
| Problem | Likely cause | Fix |
|---|---|---|
| Seedlings collapse at the base | Damping-off, favored by warm, humid, still air | Water less, add a fan, use fresh medium and clean trays |
| Fuzzy white growth on the surface | Mold from overwatering and poor ventilation; or harmless root hairs | Root hairs disappear when misted; true mold does not. Improve airflow, water from below |
| Tall, pale, floppy seedlings | Too little light after the blackout stage | Lower the light to 6–12 inches, run it about 16 hours |
| Patchy germination | Uneven sowing, dry seed, old seed, or no soak for large seeds | Sow evenly, keep covered and moist, soak large seeds |
| Yellowish leaves | Grown too long in the dark, or iron shortage in plain water | Give light sooner; Penn State noted plain water sometimes caused iron deficiency in longer crops |
Are microgreens more nutritious?
Research summarized by Penn State shows microgreens generally have higher concentrations of vitamins than the mature plants, though amounts vary widely by crop and growing conditions. Maryland Extension adds that higher light intensity increases their content of beneficial phenolic compounds. They are eaten in small amounts, so think of them as a flavorful, nutrient-dense garnish rather than a replacement for full servings of vegetables.
Want more fresh food indoors this winter? See our guides to an indoor herb garden and an indoor vegetable garden, or let a tray grow on into full plants with our guide to growing arugula.
Frequently asked questions
Do microgreens grow back after cutting?
No. Once cut, microgreens do not regrow. For a continuous supply, sow a new tray every week or so. If you want repeat cuts, grow baby greens instead: thinned to about 2 inches apart, they regrow for 1–2 more harvests.
Can I grow microgreens without soil?
Yes. Coconut coir and hydroponic mats made from hemp, jute or wood fiber all work. Keep them moist and water from below.
Can I use regular garden seeds?
You can, as long as they are untreated. Avoid seed coated with fungicide or other pesticides, which is often colored. Bulk microgreen seed is much cheaper per tray.
Sources
- University of Maryland Extension, Growing Microgreens and Baby Greens Indoors (definitions, crops, containers, media, seeding density, soaking, blackout, light, watering, temperature, yield, storage).
- Penn State Extension, Growing Microgreens (untreated seed, seeding rate, germination temperatures, harvest, yields by crop, storage at 41°F, damping-off, nutrition).
- Utah State University Extension, Grow Your Own Microgreens (crop table with seed amounts, soaking, covered days and days to harvest; weighting and blackout method).
