How to grow microgreens at home: a step-by-step guide

Microgreens are young vegetable and herb plants, cut when their first leaves open. You eat the stem and leaves, but not the root or the seed. Sprouts are a different crop, grown in water and eaten whole, as our page on microgreens vs. sprouts explains.

This is how to grow microgreens indoors, on a sunny windowsill or under a light. For the short version, see our microgreens care sheet.

How to grow microgreens at home, step by step

To grow microgreens at home, sow thick seed, keep it dark under a weight, then give it light. Most trays are ready in 1 to 3 weeks.

What you need:

• 2 shallow trays. One with holes holds the mix. One without holes sits under it and holds water. The usual size is a “1020” tray, about 10 by 20 inches. Most microgreen trays work, and a takeout box is fine for a first try.
• A mix to grow in. Use seed-starting mix, potting soil such as Fox Farm, coconut coir (shredded coconut husk), or a grow mat. Our guide to the best growing media for indoor herbs compares them.
• Seed sold for sprouting or microgreens. The safety section explains why.
• A weight of 2 to 5 pounds, such as a book or a bag of rice. You also need a spray bottle and sharp scissors.
• Light. A sunny south window works, or use a grow light. Our guide to indoor grow lights helps you pick one.

For the bottom tray, a deep solid tray like this one holds plenty of water.

1. Soak big seeds. Soak pea and sunflower seeds in clean water for 8 to 12 hours. Rinse them, then sow. Small seeds go in dry.
2. Fill the tray. Spread 1/2 to 1 inch of mix in the tray with holes. It should feel like a wrung-out sponge: wet to the touch, with no drips. Press it flat.
3. Sow thick. Scatter the seed so the seeds almost touch, in a single layer with no piles. Use the amounts in the table below. Do not cover the seed with mix, since bare seed keeps the shoots clean. Mist it well.
4. Cover it and add weight. Set the second tray right on the seeds and put 2 to 5 pounds on top. Keep it dark. The weight pushes the roots down into the mix and helps the shoots shed their seed coats. Halfway through the dark days, take off the weight. Turn the top tray upside down to make a loose lid.
5. Uncover when the shoots lift the lid. This takes 1 to 4 days for most seeds. Pale yellow shoots are normal and turn green in a day of light.
6. Give them light. Put the tray in your brightest window. Or set a grow light on a timer for 12 to 16 hours a day. Turn a window tray each day so the shoots grow straight. A small fan on low keeps the air moving. A room between 60 and 75°F suits them.
7. Water from below. Pour about 2 cups of water into the solid tray and set the tray with holes in it. After 30 minutes, tip out any water left in the bottom. Do this once a day, or when the tray feels light. Most kinds need no plant food.
8. Cut when the first true leaves show. These are the second pair of leaves, often at 2 to 3 inches tall. Cut just above the mix with clean scissors, and store the greens dry in the fridge.

Best microgreens for beginners, with days to harvest

Most easy microgreens take 6 to 12 days to grow from seed to harvest. Basil takes about 2 weeks, and cilantro takes 3 to 4 weeks. The seed amounts below are for one 10 by 20 inch tray.^[1]

Seed	Soak first?	Seed per tray	Days covered	Days to harvest
Radish	No	42 g (about 3½ tbsp)	1 to 2	8 to 12
Broccoli	No	28 g (about 2½ tbsp)	2 to 4	8 to 12
Kale	No	28 g (about 2½ tbsp)	1 to 2	8 to 12
Arugula	No	10 g (about 1 tbsp)	1 to 2	6 to 8
Pea shoots	Yes, overnight	150 g (about 5 oz)	3	8 to 10
Sunflower	Yes, overnight	48 g (about 1.7 oz)	3	9 to 10
Basil	No	28 g (1 oz)	4 to 7	12 to 16
Cilantro	No	28 g (1 oz)	7 to 14	21 to 28

For a smaller tray, cut the seed in the same ratio: half the tray, half the seed. A cool room adds a few days.

Start with radish, broccoli, or pea shoots. They come up fast and even, and they forgive uneven watering. To choose by taste, see our list of the most flavorful microgreens.

Which microgreen seeds need soaking?

Only big, hard seeds need soaking, such as pea, sunflower, and beet. Pea and sunflower need 8 to 12 hours. Beet can soak for up to 24 hours. Radish, broccoli, kale, and arugula go in dry.

Never soak basil, chia, or cress. These seeds grow a coat of clear jelly when they get wet. Soaked, they stick together in a lump you cannot spread. Sow them dry and a little thin, and mist them instead of pouring water on.

How to grow microgreens without soil

You can grow microgreens without soil on coconut coir, a grow mat, or a wet paper towel. The steps are the same. Only the watering changes.

Coconut coir. Coir is clean and light, and it holds water well. About 2 quarts of damp coir fills a 10 by 20 inch tray.

Hemp or fiber mats. Cut the mat to fit, soak it, and lay it flat in the tray. Mats dry out faster than soil, so check them twice a day. The roots grip the mat, so cut above it at harvest. Each mat is good for one crop.

Paper towel. Wet paper towel in a small dish works for small seeds such as broccoli, radish, or cress. Keep a lid on until the seeds sprout, since paper dries out fast. It is too thin for pea and sunflower.

Cress and watercress seed grow well on a wet mat. For full-size plants, see how to grow watercress indoors. Wheatgrass grows on a mat the same way, and our wheatgrass guide has the steps.

A sprouting jar grows sprouts. For microgreens, the seeds need light and a mix or mat to root in.

The easiest no-soil option: a Hamama kit

A Hamama kit swaps the mix, seed, and weight for a seed quilt. That is a thin pad of paper and coir with the seed already spaced inside. You set it on water in the tray, and it is ready in 7 to 10 days.

The kit costs $35 with a tray and 3 seed quilts. Refills run $22 for 3, or less in bulk, so each tray costs about $5 to $7. Bulk seed and mix cost far less per tray, but the kit takes out the guesswork. Our code HERBSATHOMECO takes 5% off, and this link to the Hamama microgreens kit adds it for you. Our full Hamama kit review has the details.

Is it mold or root hairs?

Fine white fuzz spread evenly over the roots is root hairs, and it vanishes when you mist it. That is normal. Gray or white webs in patches over the mix, seeds, and stems are mold.

Root hairs are tiny hairs on each root that help it drink. You see them most just after you uncover the tray, or when the mix is a little dry. Try the mist test: spray them, and they flatten and vanish, then come back as they dry. Root hairs have no smell.

Mold looks like cobweb. It grows in patches and spreads onto seed hulls and stems. It stays put when you mist it. It smells musty or rotten, and the stems go slimy or fall over.

If it is mold, do not eat from that tray. Compost it, then wash both trays in hot, soapy water. Our guide to spotting and removing mold on houseplants has more.

To stop it next time, sow a little thinner and water only from below. Run a small fan, and uncover on time.

Common microgreen mistakes and how to fix them

The most common mistakes are leaving the tray covered too long, skipping the weight, and watering from the top.

Long, pale stems that flop over. The tray stayed covered too long or got too little light. Uncover it as soon as the shoots lift the lid, and move it straight into bright light.

Seed hulls stuck on the leaves. The shoots had nothing to push against. Use the weight during the dark days. Mist the shoots when you uncover them, and rinse the greens after cutting to wash off the rest.

Stems that lean one way. They are reaching for the window. Turn the tray each day.

Bare patches and a thin tray. There was too little seed, or it went on in piles. Weigh the seed using the table above, and spread it evenly.

Watering from the top. It keeps the leaves and surface wet, and that invites mold. Water from below.

Are homegrown microgreens safe to eat?

Yes, homegrown microgreens are safe to eat, and the risk is low. From 1998 to 2017, no known US food poisoning outbreaks were linked to microgreens. Sprouts and baby greens had more than 50 in the same years.^[2] The seed itself can still carry germs, so buy the right seed and keep things clean.

• Buy seed sold for sprouting or microgreens. Never use seed labeled as treated. It has a pesticide coating, and on some kinds the seed coat stays on the shoot you eat.^[3]
• Never grow tomato, pepper, eggplant, or potato as microgreens. Their seedlings contain alkaloids, natural chemicals that are toxic in large amounts.^[4]
• Keep it clean. Wash your hands and both trays before each new batch.
• Keep soil off the greens. Cut above the mix, keep the greens cold, and rinse them just before you eat them.

Questions & answers

Do microgreens regrow after cutting?

Most do not. Compost the roots and mix, and sow a new tray. Pea shoots are the one to try. Cut them just above the lowest leaves, and you can often get a second, smaller crop.

How long do microgreens take to grow?

Most take 1 to 3 weeks from seed to harvest. Arugula, radish, broccoli, and kale are ready in 6 to 12 days. Basil takes about 2 weeks, and cilantro 3 to 4.

When should you harvest microgreens?

Harvest when the first true leaves show, usually at 2 to 3 inches tall. True leaves are the second pair, after the first seed leaves. Cut just above the mix.

How do you store microgreens?

Keep them dry and unwashed in a lidded box lined with a paper towel, in the fridge. They stay fresh for 5 to 7 days. Rinse them just before you eat them.

Can you reuse soil after growing microgreens?

Not for your next tray. The old roots mat the mix, and they can carry mold into the next crop. Compost the used mix, wash the tray, and start with fresh mix. Our guide to composting at home shows how to turn it into new soil.

Is it worth it to grow your own microgreens?

Yes, if you eat them every week. Seed for one tray costs well under $2 when you buy it in bulk. Utah State priced it at 17 cents a tray for arugula and $1.95 for purple radish in January 2026. Each tray needs only a quick check and a drink once a day.

References

1. Utah State University Extension, Grow Your Own Microgreens (seed per 1020 tray, soak, covered days, and days to harvest, Table 1). https://extension.usu.edu/yardandgarden/research/grow-your-own-microgreens ↩︎

2. University of Nevada, Reno Extension, Microgreens and Produce Safety. https://naes.unr.edu/dfi/publication.aspx?PubID=3468 ↩︎

3. Penn State Extension, Growing Microgreens. https://extension.psu.edu/growing-microgreens ↩︎

4. Penn State Extension, The ABCs of Microgreens. https://extension.psu.edu/the-abcs-of-microgreens ↩︎