Growing watermelon: timing, spacing and costs by zone

When to plant

Watermelon: warm-season, will not take a frost. Plant when soil reaches 75–95°F. Dates below are averages worked out from each zone's frost dates — check your own field.

• Zone 6b (Boone NC): set out May 8 – May 29. First picking around August 8 – September 5.
• Zone 7b (Raleigh): set out April 22 – May 13. First picking around July 23 – August 20.
• Zone 8b (Charleston SC): set out March 29 – April 19. First picking around June 29 – July 27.
• Zone 9a (Gainesville FL): set out March 11 – April 1. First picking around June 11 – July 9.

Setting it up

Direct-seed or transplant (start transplants about 3 weeks ahead). Space plants 36 inches apart in rows 96 inches apart, about 1 inch deep. Expect roughly 85 days to first harvest.

Field notes

Ripeness cue: tendril nearest the fruit turns brown and the ground spot yellows. Do not go by thumping alone.

How it fits each zone

• Zone 6b: good — Watermelon is frost-tender, so timing the outdoor transplant to the last frost matters more here than in warmer zones. Row cover buys 2 weeks of head start.
• Zone 7b: excellent — Watermelon is well suited to Zone 7b. Standard planting dates work with minor adjustments for microclimates.
• Zone 8b: excellent — Watermelon is well suited to Zone 8b. Standard planting dates work with minor adjustments for microclimates.
• Zone 9a: excellent — Watermelon is well suited to Zone 9a. Standard planting dates work with minor adjustments for microclimates.

What it costs per acre

• 2026 Watermelon Budget (University of Georgia CAES — Agricultural & Applied Economics, 2026): about $3,251 per acre in transcribed costs.
• Watermelon Production Budget for North Florida (FE1104) (UF/IFAS — Food & Resource Economics, 2021): about $4,278 per acre in transcribed costs.
• University of Delaware Seedless watermelon budget — 2026 (University of Delaware Cooperative Extension, 2026): about $6,996 per acre in transcribed costs.
• 2008 Maryland Vegetable Enterprise Budgets: Watermelon (Seeded) — Per Acre (University of Maryland Extension, 2008): about $1,967 per acre in transcribed costs.
• Irrigated Watermelon Enterprise Budget, Seedless Variety Type — Sample, 2024 (Oklahoma State University Extension, 2024): about $4,718 per acre in transcribed costs.

These are published budgets, not your costs. Plug your own numbers into the breakeven calculator before you commit ground.

Before you plant

Line up who will buy it and at what price before seed goes in the ground. See the planting calendar for your exact zone.