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When to Plant Sweet Corn in Throckmorton 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.

Throckmorton County, Texas is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 9, giving you a growing season of approximately 223 days.

At an elevation of 4,952 feet, Throckmorton County receives approximately 60.7 inches of rainfall annually with predominantly loam soil. Summer highs average 89ยฐF, providing good warmth for Sweet Corn during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Corn root diseases.

Throckmorton County, TX (Zone 7b) Long season
223 days
Last Spring Frost March 31
223 growing days
First Fall Frost November 9

Throckmorton County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (120 days to spare)
Transplant: Mar 21 🍅 Harvest: May 23 – Jul 4
Recommended (50%) ✓ Fits season (118 days to spare)
Transplant: Mar 31 🍅 Harvest: Jun 2 – Jul 14
Safe Start (90%) ✓ Fits season (116 days to spare)
Transplant: Apr 16 🍅 Harvest: Jun 18 – Jul 30

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 Throckmorton County

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

Soil pH

Your soil pH (6.5โ€“7.2) overlaps with Sweet Corn's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The loam soil in Throckmorton County is excellent for Sweet Corn โ€” good drainage, moisture retention, and nutrient holding capacity.

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 223-day season

Sow every 6.9 weeks. Last sowing by Aug 11 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 708 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€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 2.2" 0" โ„๏ธ Dormant
Mar 6.5" 4" 2.5" ๐Ÿ’ง Light watering
Apr 6.5" 5.9" 0.6" ๐Ÿ’ง Light watering
May 6.5" 8.5" 0" โœ… Rainfall sufficient
Jun 6.5" 11.2" 0" โœ… Rainfall sufficient
Jul 6.5" 7.3" 0" โœ… Rainfall sufficient
Aug 6.5" 7.9" 0" โœ… Rainfall sufficient
Sep 6.5" 4.9" 1.6" ๐Ÿ’ง Light watering
Oct 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Nov 6.5" 2.3" 4.2" ๐Ÿšฟ Regular watering
Dec โ€” 1.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Throckmorton 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 ~1,256 GDD — county provides 3,735 GDD Excellent fit

Sweet Corn Planting Timeline โ€” Throckmorton County, TX

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow April 7 Apr 7 โ€“ Apr 28
Harvest June 9 Jun 9 โ€“ Jul 21

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Direct Sow
May โ€”
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: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

223 days in Throckmorton County

Growing Tips for Sweet Corn in Throckmorton County

Direct sow Sweet Corn outdoors after March 31 in Throckmorton County when soil has warmed and frost danger has passed.

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 Throckmorton County, TX?

Throckmorton County is in Zone 7b with an average last frost of March 31. Plan your Sweet Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Throckmorton County, TX?

Throckmorton County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Throckmorton County gardeners in Zone 7b 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 Throckmorton County, TX. Local conditions may vary. Last updated: April 2026.