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When to Plant Sweet Corn in Red River 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.

Red River County, Texas is in USDA Zone 8a. The average last spring frost is March 18 and the first fall frost is November 11, giving you a growing season of approximately 238 days.

At an elevation of 314 feet, Red River County receives approximately 60.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91ยฐF, providing good warmth for Sweet Corn during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” 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.

Red River County, TX (Zone 8a) Long season
238 days
Last Spring Frost March 18
238 growing days
First Fall Frost November 11

Red River County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.4-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (134 days to spare)
Transplant: Mar 8 🍅 Harvest: May 10 – Jun 21
Recommended (50%) ✓ Fits season (133 days to spare)
Transplant: Mar 18 🍅 Harvest: May 20 – Jul 1
Safe Start (90%) ✓ Fits season (128 days to spare)
Transplant: Apr 8 🍅 Harvest: Jun 10 – Jul 22

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 Red River County

How your county's soil matches Sweet Corn's growing requirements.

Soil pH

Your soil pH (5.4โ€“6.2) is more acidic than Sweet Corn prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Red River 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

1"
Planting Depth
12"
Between Plants
36"
Between Rows

Succession Planting Sweet Corn

4
successive plantings in your 238-day season

Sow every 6.9 weeks. Last sowing by Aug 13 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.1″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 908 gal / 100 sq ft

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 โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 2" 0" โ„๏ธ Dormant
Mar 6.5" 4.2" 2.3" ๐Ÿ’ง Light watering
Apr 6.5" 6" 0.5" ๐Ÿ’ง Light watering
May 6.5" 9.8" 0" โœ… Rainfall sufficient
Jun 6.5" 8.6" 0" โœ… Rainfall sufficient
Jul 6.5" 8.6" 0" โœ… Rainfall sufficient
Aug 6.5" 8" 0" โœ… Rainfall sufficient
Sep 6.5" 5.1" 1.4" ๐Ÿ’ง Light watering
Oct 6.5" 3.9" 2.6" ๐Ÿ’ง Light watering
Nov 6.5" 1.8" 4.7" ๐Ÿšฟ Regular watering
Dec โ€” 1.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Red River County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~1,369 GDD — county provides 4,343 GDD Excellent fit

Sweet Corn Planting Timeline โ€” Red River County, TX

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow March 25 Mar 25 โ€“ Apr 15
Harvest May 27 May 27 โ€“ Jul 8

Plant 1" deep ยท 12" apart ยท Rows 36" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April Direct Sow
May Harvest
June Harvest
July Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.5"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

238 days in Red River County

Growing Tips for Sweet Corn in Red River County

Direct sow Sweet Corn outdoors after March 18 in Red River County when soil has warmed and frost danger has passed.

Sandy soil in Red River County dries quickly โ€” 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

  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Corn in Red River County, TX?

Red River County is in Zone 8a with an average last frost of March 18. Plan your Sweet Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Red River County, TX?

Red River County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 18 and first fall frost is November 11.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Red River County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Red River County, TX. Local conditions may vary. Last updated: April 2026.