When to Plant Sweet Corn in Lamar 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.
Lamar County, Texas is in USDA Zone 7b. The average last spring frost is March 15 and the first fall frost is November 15, giving you a growing season of approximately 245 days.
At an elevation of 95 feet, Lamar County receives approximately 59.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91°F, providing good warmth for Sweet Corn during the growing season. Sandy soil warms quickly in spring — great for early planting — but Sweet Corn will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Corn root diseases.
Lamar County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.8-6.8
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 Lamar County
How your county's soil matches Sweet Corn's growing requirements.
Soil pH
Your soil pH (5.8–6.8) overlaps with Sweet Corn's range (6.0–7.0), though not a perfect match.
Soil Texture
Sandy soil in Lamar County warms quickly in spring but drains fast. Sweet Corn will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (1.9%). Add 2-3 inches of compost before planting Sweet Corn.
How to Plant Sweet Corn
Succession Planting Sweet Corn
Sow every 6.9 weeks. Last sowing by Aug 17 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 6.5" | 3.5" | 3" | 💧 Light watering |
| Apr | 6.5" | 6.8" | 0" | ✅ Rainfall sufficient |
| May | 6.5" | 8.8" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 9.7" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 8" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 7.1" | 0" | ✅ Rainfall sufficient |
| Sep | 6.5" | 5.3" | 1.2" | 💧 Light watering |
| Oct | 6.5" | 3.4" | 3.1" | 💧 Light watering |
| Nov | 6.5" | 2.2" | 4.3" | 🚿 Regular watering |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Lamar 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 — Lamar County, TX
Sweet Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 22 | Mar 22 – Apr 12 |
| Harvest | May 24 | May 24 – Jul 5 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| 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 7b
📆 Growing Season
245 days in Lamar County
Growing Tips for Sweet Corn in Lamar County
Direct sow Sweet Corn outdoors after March 15 in Lamar County when soil has warmed and frost danger has passed.
Sandy soil in Lamar County dries quickly — mulch Sweet Corn with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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 Lamar County, TX?
Lamar County is in Zone 7b with an average last frost of March 15. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lamar County, TX?
Lamar County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 15 and first fall frost is November 15.
Plan Your Garden with Confidence
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