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When to Plant Corn in Dallas County, TX

Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

Dallas County, Texas is in USDA Zone 8a. The average last spring frost is March 8 and the first fall frost is November 20, giving you a growing season of approximately 257 days.

At an elevation of 67 feet, Dallas County receives approximately 65.7 inches of rainfall annually with predominantly clay soil. Summer highs average 97ยฐF, so Corn may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Corn, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Corn root diseases.

Dallas County, TX (Zone 8a) Long season
257 days
Last Spring Frost March 8
257 growing days
First Fall Frost November 20

Dallas County Soil Profile

Soil Type

Clay

Soil pH

6.7-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (135 days to spare)
Transplant: Mar 1 🍅 Harvest: May 3 – Jun 28
Recommended (50%) ✓ Fits season (138 days to spare)
Transplant: Mar 8 🍅 Harvest: May 10 – Jul 5
Safe Start (90%) ✓ Fits season (123 days to spare)
Transplant: Apr 9 🍅 Harvest: Jun 11 – Aug 6

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 Dallas County

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

Soil pH

Your soil pH (6.7โ€“8.4) is more alkaline than Corn prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Heavy clay soil (48% clay) in Dallas County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Corn.

How to Plant Corn

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

Succession Planting Corn

5
successive plantings in your 257-day season

Sow every 6.9 weeks. Last sowing by Aug 12 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 975 gal / 100 sq ft

Monthly Watering Guide for Corn

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 Corn Needs Rainfall You Supplement Action
Jan โ€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 2.5" 0" โ„๏ธ Dormant
Mar 6.5" 4.4" 2.1" ๐Ÿ’ง Light watering
Apr 6.5" 7.1" 0" โœ… Rainfall sufficient
May 6.5" 9.2" 0" โœ… Rainfall sufficient
Jun 6.5" 10.4" 0" โœ… Rainfall sufficient
Jul 6.5" 7.4" 0" โœ… Rainfall sufficient
Aug 6.5" 8.3" 0" โœ… Rainfall sufficient
Sep 6.5" 6" 0.5" ๐Ÿ’ง Light watering
Oct 6.5" 4.6" 1.9" ๐Ÿ’ง Light watering
Nov 6.5" 2.4" 4.1" ๐Ÿšฟ Regular watering
Dec โ€” 1.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Dallas County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

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.

Corn needs ~1,820 GDD — county provides 5,846 GDD Excellent fit

Corn Planting Timeline โ€” Dallas County, TX

Corn Planting Calendar

Activity When Date Range
Direct Sow March 15 Mar 15 โ€“ Apr 5
Harvest May 17 May 17 โ€“ Jul 12

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€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

257 days in Dallas County

Growing Tips for Corn in Dallas County

Direct sow Corn outdoors after March 08 in Dallas County when soil has warmed and frost danger has passed.

With Dallas County's clay soil (48% clay), work in 3-4 inches of compost before planting Corn. Avoid tilling when soil is wet to prevent compaction.

With summer highs reaching 97ยฐF in Dallas County, provide afternoon shade for Corn and water deeply in the morning.

Common pests for 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 rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Recommended Corn Varieties for Dallas County

Heat-tolerant varieties that silk well in high temps

Silver Queen (92d) Incredible (85d)

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in Dallas County, TX?

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

What planting zone is Dallas County, TX?

Dallas County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 8 and first fall frost is November 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Dallas 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 Dallas County, TX. Local conditions may vary. Last updated: April 2026.