Short answer: soak about 25 to 35 g of radish seed for 4 to 8 hours (optional). Sow it evenly on a 10 × 20 inch tray of moist potting mix, then mist it and cover it. Keep it dark for 2 to 3 days. Uncover, give bright light and water from below daily. Cut just above the soil at 10 to 12 days, when the seed leaves are open.
Why grow radish microgreens?
- Fast and reliable. Radish sprouts in a day or two and rarely fails, which makes it a top beginner microgreen.
- Big flavour. Hot, peppery and crisp, with a juicy stem.
- Colour. Red and purple varieties add colour to any plate.
- Nutrients. In a USDA study of 25 microgreens, green daikon radish was among the highest in vitamin E.1
What you need
- Radish seed sold for sprouting or microgreens
- A 10 × 20 inch tray set, one with holes and one without
- About 1 inch (2.5 cm) of fine potting mix, coco coir or a grow mat
- A cover: a spare tray works
- A spray bottle, sharp scissors, and a bright window or LED light
How much seed to use
For a 10 × 20 inch tray, use about 25 to 35 g of radish seed. For a 10 × 10 tray, use about half. Radish seed is large, so it needs more weight per tray than small seeds like broccoli. Spread it so the seeds touch but don't pile up.
How to grow radish microgreens, day by day
- Day0
Soak (optional)
Soak the seed in cool water for 4 to 8 hours, then drain it. This speeds up germination.
- Day0
Sow
Fill the holed tray with about 1 inch of moist potting mix and press it flat. Spread the seed evenly and press it lightly into the surface. Mist well.
- Day0–3
Blackout
Cover the tray with another tray. Mist once or twice a day. Some growers add a light weight on top for stronger, straighter stems.
- Day2–3
Uncover
When the seedlings push up the cover, take it off. Move the tray to bright light for 12 to 16 hours a day.
- Day3–10
Water from below
Pour water into the solid tray once a day. Let the roots drink for 10 to 15 minutes, then tip out the rest.
- Day10–12
Harvest
Cut just above the soil with sharp scissors when the seed leaves are fully open.
Fuzzy roots are normal. Radish grows lots of fine white root hairs on day 2 or 3. Mist them. If the fuzz collapses, it's root hairs, not mold.
Best radish varieties for microgreens
| Variety | Look | Flavour |
|---|---|---|
| Red radish | Green leaves, pink stems | Classic hot radish |
| Rainbow radish blend | Mixed pink, purple, green stems | Peppery, colourful |
| Ruby Stem | Bright red stems | Mild to medium |
| Triton | Purple leaves and stems | Spicy |
| China Rose | Pink stems, larger leaves | Hot, strong |
| Daikon | Green leaves, white stems | Crisp and spicy |
Every variety grows the same way. Purple types like Triton show the best colour under strong light.
Radish microgreens problems and fixes
| Problem | Likely cause | Fix |
|---|---|---|
| Mold at the base | Too thick, too wet, still air | Sow a bit thinner, water from below, add a small fan |
| Tall, pale, floppy | Not enough light | Use a brighter window or bring an LED light closer |
| Uneven growth | Uneven sowing | Spread seed carefully. Press it flat |
| Hulls on leaves | Dry blackout | Mist well before uncovering, brush hulls off at harvest |
| Very hot taste | Harvested late | Cut a day or two earlier |
How to eat radish microgreens
- Tacos and burritos: a hot, crunchy topping.
- Sandwiches: in place of lettuce or with egg salad.
- Sushi and rice bowls: they pair well with soy and sesame.
- Salads: mix them with milder greens. See microgreen mixes.
- Avocado toast and eggs: scatter them on just before serving.
Store dry radish microgreens in a container lined with a paper towel in the fridge. They keep about 5 to 7 days. Read how to store microgreens.
Radish sprouts or radish microgreens?
The same seed also makes radish sprouts in a jar in 4 to 5 days. Sprouts are eaten whole, roots and all. Microgreens grow in soil with light and are cut above the roots. They have bigger leaves and a stronger flavour. See microgreens vs sprouts.
We link to radish seed and the Spicy Microgreen Blend from Sprouting.com, a mix of mustard, arugula and cress that pairs well with radish.
Seeds in this article
Frequently asked questions
How long do radish microgreens take to grow?
About 10 to 12 days from sowing, per Sprouting.com. In a warm room with good light, some growers cut them as early as day 8. Harvest when the seed leaves are fully open.
Do you soak radish seeds for microgreens?
Soaking is optional but helps. A soak of 4 to 8 hours makes the seed sprout faster and more evenly. You can also sow it dry on moist soil and mist well.
How much radish seed do I need per tray?
About 25 to 35 g for a 10 × 20 inch tray, or roughly half that for a 10 × 10 tray. Radish is a big seed, so it needs more weight per tray than broccoli.
Do radish microgreens regrow after cutting?
No. Radish microgreens don't grow back once cut. Compost the roots and soil, and sow a new tray. Starting a small tray every few days keeps a steady supply.
Why are my radish microgreens spicy?
Radish greens are naturally hot, like the root. Varieties differ, and older greens get hotter. For milder greens, cut them a day or two early.
Written by Michael
A passionate sprouting professional sharing practical tips for growing sprouts and microgreens at home. More about Michael
Sources
- Xiao Z, Lester GE, Luo Y, Wang Q. Assessment of vitamin and carotenoid concentrations of emerging food products: edible microgreens. Journal of Agricultural and Food Chemistry, 2012. Link
