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When to Plant Sweet Corn in Irion 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.

Irion County, Texas is in USDA Zone 7b. The average last spring frost is April 1 and the first fall frost is November 7, giving you a growing season of approximately 220 days.

At an elevation of 1,818 feet, Irion County receives approximately 51.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 100ยฐF, so Sweet Corn may need afternoon shade and extra watering during peak heat. 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.

Irion County, TX (Zone 7b) Long season
220 days
Last Spring Frost April 1
220 growing days
First Fall Frost November 7

Irion County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.6-8.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Transplant: Mar 21 🍅 Harvest: May 23 – Jul 4
Recommended (50%) ✓ Fits season (115 days to spare)
Transplant: Apr 1 🍅 Harvest: Jun 3 – Jul 15
Safe Start (90%) ✓ Fits season (117 days to spare)
Transplant: Apr 15 🍅 Harvest: Jun 17 – Jul 29

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 Irion County

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

Soil pH

Your soil pH (7.6โ€“8.6) is more alkaline than Sweet Corn prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Irion 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 (1.0%). 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 220-day season

Sow every 6.9 weeks. Last sowing by Aug 09 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.0″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,219 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Sweet Corn needs ~1,875 GDD — county provides 5,500 GDD Excellent fit

Sweet Corn Planting Timeline โ€” Irion County, TX

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow April 8 Apr 8 โ€“ Apr 29
Harvest June 10 Jun 10 โ€“ Jul 22

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: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

220 days in Irion County

Growing Tips for Sweet Corn in Irion County

Direct sow Sweet Corn outdoors after April 01 in Irion County when soil has warmed and frost danger has passed.

Sandy soil in Irion 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.

With summer highs reaching 100ยฐF in Irion 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

  • Tomatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Sweet Corn in Irion County, TX?

Irion County is in Zone 7b with an average last frost of April 1. Plan your Sweet Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Irion County, TX?

Irion County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is April 1 and first fall frost is November 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Irion County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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