When to plant watermelons 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). Watermelon needs 70–100 days to mature, which fits comfortably within South Carolina's growing season.
When to plant watermelons in South Carolina: the short answer
For a spring planting, plant out Apr 1 – Apr 18, with seeds started indoors Feb 25 – Mar 11. Wait until the soil is at least 70°F and frost is over.
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 watermelons in South Carolina, step by step
- Start seeds indoors (Feb 25 – Mar 11). Sow seeds 1 inch deep in seed-starting mix under bright light. They take 4-10 days to sprout, fastest in soil around 85°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. They need at least six to eight hours of direct sun a day and loose soil at least 24 inches deep, with a pH between 5.5 and 6.8. Dig in compost before planting.
- Plant out (Apr 1 – Apr 18). Space plants about 36 inches apart in rows 72 inches apart. It is killed by frost, so nothing goes outside until the danger has passed.
- 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: striped cucumber beetle, aphids, squash vine borer. Diseases and disorders: anthracnose, fusarium wilt, powdery mildew, gummy stem blight.
- Harvest (from about Jun 17 – Jul 17). Watermelon takes 70-100 days to reach harvest. Longest-season cucurbit here - icebox varieties (70-75 days) are the realistic choice north of the mid-Atlantic. Ripe when the curly tendril nearest the fruit is brown and dry and the ground spot is buttery yellow.
Figures come from our crop data; dates use South Carolina’s average frost dates. More in the full watermelon growing guide.
Watermelon 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 watermelon dates shift with them.
When to plant watermelons in nearby states
| State | Last frost | Plant out |
|---|---|---|
| South Carolina (this page) | March 25 | Apr 1 – Apr 18 |
| North Carolina | April 5 | Apr 12 – Apr 29 |
| Georgia | March 25 | Apr 1 – Apr 18 |
| Tennessee | April 10 | Apr 17 – May 4 |
| Kentucky | April 18 | Apr 25 – May 12 |
Questions gardeners in South Carolina ask
When is the best time to plant watermelons in South Carolina?
Plant watermelon transplants outdoors in South Carolina between April 1 and April 18. That timing is set by South Carolina's average last spring frost of March 25.
When should I start watermelon seeds indoors in South Carolina?
Start seeds indoors between February 25 and March 11, about 3 weeks before the last frost, so the seedlings are ready to plant out from April 1.
What is the latest I can plant watermelons in South Carolina?
About August 27. Watermelons need at least 70 days to mature, and frost around November 5 ends the season, so later plantings risk being cut short.
When will watermelons planted in South Carolina be ready to harvest?
Planted on time, watermelons are usually ready from about June 17 to July 17, 70-100 days after planting.
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.