When to plant sweet potatoes in USDA Zone 9b

Plan your sweet potatoes 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.

Orlando, Tampa, San Antonio, southern LA coast. Average last spring frost February 5, first fall frost December 15 — a 313-day frost-free season.

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

Key dates

Start seeds indoors
December 18 – January 1
Transplant outdoors
February 19 – March 12
Expected first harvest
June 6 – July 4

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
42″
Seed depth
4″
Soil temperature
75–90°F
Frost tolerance
tender
Days to harvest
100 days

Grower notes for Zone 9b

Set slips on 6–8 inch hills for better tuber shape. Cure at 85°F and 85% humidity for 7–10 days after harvest.

Plant near: beans, peas

Keep away from: squash

Other root crops for Zone 9b

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.