How to grow Radish Microgreens
Updated October 2026
Radish microgreens are among the fastest and easiest microgreens to grow indoors, ready to cut in about a week to ten days with a sharp, peppery bite. They grow on a shallow tray of moist potting mix on a bright windowsill or under a light, so you can sow them in any month anywhere in the country. Clean trays, food-grade seed and good air flow are the keys to success.
📖 Our full guide: How to Grow Radish Microgreens
Not to be confused with: Microgreens are not sprouts. Sprouts are germinated seeds eaten whole, roots and all, after a few days in water; microgreens grow in a mix under light and only the leafy stems are cut. This page is about microgreens; garden radishes grown for their roots have their own page.
Where to plant
Grow radish microgreens indoors, at room temperature, on a bright windowsill or under fluorescent or LED grow lights. Good air movement around the tray helps prevent mold. Because they are grown indoors, the calendar is the same for every region: sow in any month.
Choosing a variety
Use untreated, uncoated seed meant for eating or for microgreens, not garden seed coated with fungicide. Daikon types are the usual choice for their speed and peppery flavor and red- or purple-stemmed radishes add color.
How to plant
- Wash your hands and use a new or cleaned tray and clean tools.
- Fill the tray with about 1 to 2 inches of moist soilless potting mix, or lay a growing mat, and level the surface.
- Scatter seed thickly and evenly so the seeds nearly touch, and press them lightly into the surface.
- Cover the tray, or slip it into a loose plastic bag, to keep the humidity high for the first two or three days while the seeds root.
- Once the shoots stand up, uncover the tray and move it into bright light.
Watering and feeding
Water from below by setting the tray in a larger container of water until the mix is moist to the top, then let it drain. This keeps the seed in place and the leaves dry. Keep the mix moist but never soggy, since standing water and still air lead to mold and damping off.
Radish microgreens need no fertilizer for a single short crop.
Harvesting
Cut the shoots with clean scissors just above the mix once the seed leaves have opened, usually 7 to 10 days after sowing. Some growers wait for the first true leaf, which gives more bulk but a stronger bite. Radish microgreens do not regrow, so cut the whole tray at once.
Rinse, dry thoroughly and store in a covered container in the fridge. They are best within a few days.
Using it
Add them raw to sandwiches, tacos, salads, eggs, sushi bowls and soups just before serving. Their peppery flavor fades with cooking.
Pests and diseases
Indoors, there are no real pests. The only common problem is mold or damping off from overwatering and stale air.
Radish Microgreens is rarely troubled by pests.
Diseases to watch for
- Damping off Seedlings collapse in patches at the base, often with gray or white fuzzy mold. Water from below, improve air flow and use a clean tray next time.
Common questions
Is the white fuzz on my radish microgreens mold?
Usually not. Radish seedlings grow fine white root hairs along the roots, which look fuzzy. Root hairs sit evenly along each root. True mold looks like gray or white cobweb spreading across the mix and seed, and often smells musty.
How long do radish microgreens take?
About 7 to 10 days from sowing, once the seed leaves open. Some growers let them go a few days longer for a true leaf.
Can I use regular garden radish seed?
Only if it is untreated. Many garden seeds are coated with fungicide, which is not safe to eat. Buy untreated seed sold for microgreens or sprouting.
Do radish microgreens grow back after cutting?
No. Cut the whole tray, compost the roots and mix, and sow a fresh tray for the next crop.
Do microgreens need a grow light?
A very bright, sunny window works, but a simple LED or fluorescent light a few inches above the tray gives sturdier, greener shoots, especially in winter.
What is the difference between sprouts and microgreens?
Sprouts are germinated seeds eaten whole after a few days in water. Microgreens are grown in a mix or mat under light, and only the stems and leaves are cut and eaten.
Sources we checked: South Dakota State University Extension: Growing microgreens at home; The Garden Professors: Tiny plants that pack a flavor and nutrition punch.
More guides for radish microgreens
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