When to Plant Sweet Corn in Zapata County, TX
May in Zapata County, Texas — your action list
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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It's harvest week for sweet corn
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
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.
Zapata County, Texas is in USDA Zone 9b. The average last spring frost is February 3 and the first fall frost is December 14, giving you a growing season of approximately 314 days.
At an elevation of 3,340 feet, Zapata County receives approximately 60.6 inches of rainfall annually with predominantly loam soil. Summer highs average 103°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.
Zapata County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.6
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.
Soil Compatibility in Zapata County
How your county's soil matches Sweet Corn's growing requirements.
Soil pH
Your soil pH (6.2–7.6) overlaps with Sweet Corn's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Zapata County is excellent for Sweet Corn — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Sweet Corn.
How to Plant Sweet Corn
Succession Planting Sweet Corn
Sow every 6.9 weeks. Last sowing by Sep 15 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Sweet Corn
Sweet Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Sweet Corn Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | 6.5" | 2.3" | 4.2" | 🚿 Regular watering |
| Mar | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Apr | 6.5" | 6.3" | 0.2" | 💧 Light watering |
| May | 6.5" | 7.6" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 10.1" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 8.6" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 7.4" | 0" | ✅ Rainfall sufficient |
| Sep | 6.5" | 6.1" | 0.4" | 💧 Light watering |
| Oct | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| Nov | 6.5" | 2" | 4.5" | 🚿 Regular watering |
| Dec | 6.5" | 1.3" | 5.2" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Zapata County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sweet Corn Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Sweet Corn Planting Timeline — Zapata County, TX
Sweet Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 10 | Feb 10 – Mar 3 |
| Harvest | April 14 | Apr 14 – May 26 |
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 | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 9b
📆 Growing Season
314 days in Zapata County
Growing Tips for Sweet Corn in Zapata County
Direct sow Sweet Corn outdoors after February 03 in Zapata County when soil has warmed and frost danger has passed.
With summer highs reaching 103°F in Zapata County, provide afternoon shade for Sweet Corn and water deeply in the morning.
Common pests for Sweet Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Sweet Corn in Other Locations
Frequently Asked Questions
When should I plant Sweet Corn in Zapata County, TX?
Zapata County is in Zone 9b with an average last frost of February 3. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Zapata County, TX?
Zapata County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 3 and first fall frost is December 14.
Your Zapata County Garden Planner — Free
A 24-page printable planner built for Zapata County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.