When to plant watermelon in USDA Zone 8b

Plan your watermelon planting around local frost risk and soil temperature, then work backward from the harvest week your buyers need. The calendar below is a starting point, not a field-level weather forecast.

Charleston SC, Savannah, Mobile, Austin, Jacksonville. Average last spring frost March 15, first fall frost November 15 — a 245-day frost-free season.

Zone fit: excellent
Watermelon is well suited to Zone 8b. Standard planting dates work with minor adjustments for microclimates.

Key dates

Start seeds indoors
February 15 – March 1
Direct-seed or transplant outdoors
March 29 – April 19
Expected first harvest
June 29 – July 27

Windows are calculated from your zone's average frost dates. Adjust ±1 week for microclimates, elevation, and your own frost records.

Spacing and soil

Plant spacing
36″
Row spacing
96″
Seed depth
1″
Soil temperature
75–95°F
Frost tolerance
tender
Days to harvest
85 days

Grower notes for Zone 8b

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

Plant near: corn, radish

Keep away from: potatoes

Other cucurbits for Zone 8b

Same crop, other zones

Track your own plantings

BAU Farm Intelligence turns these windows into per-field tasks — indoor seed-start reminders, transplant dates, harvest projections — using your farm's actual frost history.