How to grow Radish

Where to plant

Radishes grow best in loose, moist, well-drained soil. Heavy, rocky or compacted soil gives small, misshapen roots, so add compost or use a raised bed if your soil is hard. Full sun is best in cool weather; a little afternoon shade helps late spring sowings.

Radishes prefer the cool temperatures of spring and fall. Hot weather and leaving roots too long make them spicy, woody or pithy, and long warm days make plants flower and go to seed.

• Florida and the Gulf South: sow from September through February. In South Florida, October to January.
• Texas, the Desert Southwest and Southern California: sow from fall into early spring, avoiding the summer heat.
• Mid-South, Mid-Atlantic, Southern Plains and the Pacific Northwest: sow in late winter to spring, and again from late summer into fall.
• Northeast, Midwest, Mountain West and Northern Plains: sow from early spring, every 7 to 10 days until late spring, then again from early August into mid-September for fall radishes. Iowa State suggests early April to mid-May and mid-August to mid-September there.
• Northern California and Hawaii: a long cool-season window from fall to spring.
• Alaska: sow from May to July.

Choosing a variety

• Round red spring radishes such as Cherry Belle are the quickest, ready in about three to four weeks.
• French Breakfast is a mild, elongated red and white heirloom.
• Daikon and other large winter radishes take 50 to 60 days and are milder. Many gardeners prefer them sown in late summer and harvested in fall.

How to plant

1. Sow seed directly where it is to grow, 1/4 to 1/2 inch deep, in rows about 12 inches apart. Radishes do not transplant well.
2. Keep the soil moist; seedlings come up within about a week.
3. Thin seedlings to 2 inches apart, or 4 to 6 inches for daikon. Crowded radishes make leaves but no roots.
4. Sow a short row every 7 to 10 days for a steady supply instead of one big harvest.

Watering and feeding

Radishes need about an inch of water a week from rain or watering. Steady moisture gives quick, crisp, mild roots; dry spells make them hot and woody, and heavy watering after a dry spell splits them.

They need little feeding. In poor soil, rake in a light dressing of an all-purpose fertilizer before sowing; too much nitrogen gives leaves instead of roots.

Harvesting

Pull spring radishes as soon as they reach full size, about an inch across for round types. Lift one to check. Left in the ground, they quickly crack, turn pithy and get too hot, so harvest each sowing over a short window.

Pull daikon and winter radishes when they reach the size for their variety. They hold in the cool fall soil longer than spring types.

Twist off the tops and keep radishes in the fridge in a bag; they keep about a week, and winter radishes far longer.

Growing in pots

Radishes are ideal for pots and window boxes. Use regular potting mix in a container at least 6 inches deep (deeper for daikon), give full sun, and keep the mix evenly moist.

Using it

Slice spring radishes into salads or eat them with butter and salt. Daikon is pickled, grated, added to soups and stir-fries, and used for kimchi. Young radish leaves and the crisp seed pods of bolted plants are edible too.