When to Plant Radishes in South Carolina
Published: April 24, 2026
South Carolina gardeners in Zone 7b have a 38-week growing season for radish (March 1 to November 22). South Carolina's spring and fall windows both work well for radish — some gardeners plant both successions for a long harvest. This guide gives exact dates for South Carolina based on your local frost calendar.
Radish Planting Dates for South Carolina
| Start seeds indoors | Year-round |
| Last frost (average) | March 1 |
| Direct sow outdoors | January 25–February 4 |
| Expect first harvest | February 16 – February 24 |
| Fall crop start | October 18–28 |
| Fall harvest | November 9 |
| First fall frost (average) | November 22 |
Dates above assume Zone 7b, the most common zone in South Carolina. Gardeners in cooler Columbia (Zone 7b) plant 1–2 weeks later; warmer Charleston (Zone 9a) can plant 1–2 weeks earlier.
⚠ Direct sow radishes 4–6 weeks before last frost — one of the fastest crops in the garden. Ready in as little as 22 days. Succession plant every 2 weeks for continuous harvest.
Growing Radishes in South Carolina's Climate
South Carolina's moderate Zone 7b climate is well-suited to radish with minimal special accommodation. The standard transplant calendar works as written, and harvest windows line up with what seed packets recommend without adjustment.
Succession planting extends your radish harvest significantly in South Carolina. A second planting 3 to 4 weeks after the first gives you a backup in case of pest pressure and extends the total harvest window into early fall.
Common radish pests to watch for in South Carolina include Flea Beetle and Cabbage Root Maggot. The first line of defense is companion planting: Lettuce and Carrot planted nearby discourage several of these pests by confusing host-plant identification or repelling adults before they can lay eggs. Weekly garden walks in the early morning catch problems when they're still manageable.
Radish Garden Calendar for South Carolina
| Month | Task | Notes |
|---|---|---|
| January | Direct sow seeds | Sow seeds 1/4–1/2 inch deep, 2 inches apart |
| February | First harvest window opens | Radish begins producing 22–30 days after transplant |
| March | — | Dormant season |
| April | — | Dormant season |
| May ← | Watch for bolting | Harvest promptly; spring heat arrives quickly |
| June | — | Dormant season |
| July | — | Dormant season |
| August | — | Dormant season |
| September | — | Dormant season |
| October | Fall crop planting | Transplant or direct sow for fall harvest before frost |
| November | First frost approaches | Harvest remaining radish; cover plants on frost nights |
| December | — | Dormant season |
Radish Growing Tips for South Carolina Gardeners
- •Thin to 2-inch spacing when seedlings are an inch tall — crowded radishes produce small woody roots.
- •Succession plant every 10–14 days from early spring through late spring for continuous harvest.
- •South Carolina's moderate climate supports succession planting — sow new transplants or seeds every 3 weeks during spring to extend the harvest window into fall.
- •Plant as a row marker for slow-germinating crops like carrots — radishes sprout in days and mark the rows.
Companion Planting for Radishes in South Carolina
In South Carolina's moderate climate, planting radish with Lettuce and Carrot helps deter pests and improve soil. Avoid planting near Hyssop and Grape, which inhibit radish growth through root chemistry or shared pest pressure. See the full radish companion planting guide for the complete list.
Radishes Planting Dates by City in South Carolina
Top cities in South Carolina — select for city-level frost dates and planting calendars.
Frequently Asked Questions
When should I plant radish in South Carolina?
In South Carolina (Zone 7b), start radish seeds indoors around Year-round and transplant outdoors around null — 0 weeks after the state's average last frost of March 1.
What is the last frost date in South Carolina?
South Carolina's average last frost date is March 1 in the state's most common Zone 7b. Frost dates vary by city — higher elevations and northern counties run 1 to 3 weeks later than the state average. See the city list below for city-level frost dates.
Can I grow radish year-round in South Carolina?
radish is a cool-season crop in South Carolina, with spring and fall windows. Summer heat bolts the plants before they can produce a harvestable crop. Succession planting every 2–3 weeks stretches the harvest window.
What radish varieties grow best in South Carolina?
For South Carolina's Zone 7b, consult a local nursery or extension office for radishes variety recommendations.
When do I start radish seeds indoors in South Carolina?
Radish does not need indoor starting in South Carolina — direct sow around January 25–February 4 once soil reaches 40°F. Indoor starting is not recommended for this crop because radish transplants poorly.