When to plant sweet corn in USDA Zone 9a

Plan your sweet corn 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.

Gainesville FL, Houston, New Orleans, southern GA coast. Average last spring frost February 25, first fall frost December 1 — a 279-day frost-free season.

Zone fit: excellent
Sweet corn is well suited to Zone 9a. Standard planting dates work with minor adjustments for microclimates.

Key dates

Direct-seed outdoors
February 25 – March 18
Expected first harvest
May 18 – June 15
Fall planting window
September 1 – September 22
Fall harvest window
November 22 – December 20

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
12″
Row spacing
30″
Seed depth
1.5″
Soil temperature
65–85°F
Frost tolerance
tender
Days to harvest
75 days

Grower notes for Zone 9a

Plant in blocks of 4+ rows for wind pollination. Isolate super-sweet varieties from standard varieties by 250 ft or 14 days.

Plant near: beans, squash, cucumbers

Keep away from: tomatoes

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.