When to plant radishes in South Carolina
South Carolina’s average last spring frost is March 25, and the first fall frost typically arrives around November 5 — about 225 frost-free days (USDA zones 7a, 7b, 8a, 8b, 9a). Radish needs 22–30 days to mature, which fits comfortably within South Carolina's growing season.
When to plant radishes in South Carolina: the short answer
For a spring planting, sow Feb 20 – Mar 11. Seeds germinate in soil from 40 to 85°F.
Succession sow again in South Carolina: Mar 7 · Mar 17 · Mar 27 · Apr 6 · Apr 16 · Apr 26
Spring succession stops before summer heat makes it bolt. Start sowing again in late summer for a fall crop (see the fall window above).
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow radishes in South Carolina, step by step
- Prepare the bed. They need six or more hours of sun for the best growth, though four to six hours in partial shade is enough and loose soil at least 6 inches deep, with a pH between 6.0 and 7.0. Dig in compost before planting.
- Sow outdoors (Feb 20 – Mar 11). Space plants about 2 inches apart in rows 6 inches apart, sowing seed ½ inch deep. It handles frost well, so it can go out before the last frost date. As a cool-season crop it does best before summer heat arrives in South Carolina.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: flea beetle, cabbage root maggot, aphids. Diseases and disorders: clubroot, scab, downy mildew.
- Harvest (from about Mar 19 – Mar 27). Radish takes 22-30 days to reach harvest. The classic marker crop and quick filler. Sow a short row every 10 days - a single big sowing all matures at once and then goes pithy and hot.
Figures come from our crop data; dates use South Carolina’s average frost dates. More in the full radish growing guide.
Radish planting dates by USDA zone in South Carolina
South Carolina spans USDA zones 7a, 7b, 8a, 8b, 9a. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the radish dates shift with them.
When to plant radishes in nearby states
| State | Last frost | Sow |
|---|---|---|
| South Carolina (this page) | March 25 | Feb 20 – Mar 11 |
| North Carolina | April 5 | Mar 3 – Mar 22 |
| Georgia | March 25 | Feb 20 – Mar 11 |
| Tennessee | April 10 | Mar 8 – Mar 27 |
| Kentucky | April 18 | Mar 16 – Apr 4 |
Questions gardeners in South Carolina ask
When is the best time to plant radishes in South Carolina?
Sow radishes in South Carolina between February 20 and March 11. That timing is set by South Carolina's average last spring frost of March 25.
Can I plant radishes in the fall in South Carolina?
Yes. For a fall crop, sow between September 21 and October 8, so the crop matures in cool weather before South Carolina's first frost around November 5.
When will radishes planted in South Carolina be ready to harvest?
Planted on time, radishes are usually ready from about March 19 to March 27, 22-30 days after sowing.
When is the last frost in South Carolina?
On average around March 25, with the first fall frost around November 5 - about 225 frost-free days. Your town may differ by two weeks or more.