When to Plant Sweet Corn in Duval County, TX
Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.
Duval County, Texas is in USDA Zone 9a. The average last spring frost is February 13 and the first fall frost is December 9, giving you a growing season of approximately 299 days.
At an elevation of 4,259 feet, Duval County receives approximately 55.2 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Sweet Corn may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Corn root diseases.
Duval County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.3
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Sweet Corn Planting Timeline — Duval County, TX
Sweet Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 20 | Feb 20 – Mar 13 |
| Harvest | April 24 | Apr 24 – Jun 5 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | Direct Sow |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
60–90 days
Soil pH
6 – 7
USDA Zone
Zone 9a
Growing Season
299 days
Growing Tips for Duval County
Plant in blocks of at least 4 rows for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Sweet Corn in Other Locations
Frequently Asked Questions
When should I plant Sweet Corn in Duval County, TX?
Duval County is in Zone 9a with an average last frost of February 13. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Duval County, TX?
Duval County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 13 and first fall frost is December 9.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Duval County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
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