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When to Plant Corn in Seminole County, OK

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.

Seminole County, Oklahoma is in USDA Zone 7a. The average last spring frost is March 31 and the first fall frost is November 6, giving you a growing season of approximately 220 days.

At an elevation of 961 feet, Seminole County receives approximately 20.7 inches of rainfall annually with predominantly loam soil. Summer highs average 94Β°F, providing good warmth for Corn during the growing season.

Seminole County, OK (Zone 7a) Long season
220 days
Last Spring Frost March 31
220 growing days
First Fall Frost November 6

Seminole County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.5

Drainage

Well Drained

How Much Corn to Grow

1-2 ears
Average yield per plant
15
Plants per person
30 sq ft
Space per person

For a family of 4, plant approximately 60 corn plants in about 120 sq ft. In Seminole County's 220-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Corn

Corn needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Corn Needs Rainfall You Supplement Action
Jan β€” 0.6" 0" ❄️ Dormant
Feb β€” 0.8" 0" ❄️ Dormant
Mar 4.3" 1.4" 2.9" 🚿 Regular watering
Apr 4.3" 2.1" 2.2" 🚿 Regular watering
May 4.3" 3.2" 1.1" πŸ’§ Light watering
Jun 4.3" 3.3" 1" πŸ’§ Light watering
Jul 4.3" 2.4" 1.9" πŸ’§ Light watering
Aug 4.3" 2.8" 1.5" πŸ’§ Light watering
Sep 4.3" 1.7" 2.6" 🚿 Regular watering
Oct 4.3" 1.3" 3" 🚿 Regular watering
Nov 4.3" 0.8" 3.5" 🚿 Regular watering
Dec β€” 0.5" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Seminole County). Supplement amounts are based on average rainfall β€” actual needs vary with temperature, soil, and mulching.

Corn Planting Timeline β€” Seminole County, OK

Corn Planting Calendar

Activity When Date Range
Direct Sow April 7 Apr 7 – Apr 28
Harvest June 9 Jun 9 – Aug 4

Plant 1" deep Β· 12" apart Β· Rows 36" apart

Month-by-Month Timeline

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

Growing Conditions

β˜€οΈ Sun

Full Sun (6-8+ hours)

πŸ’§ Water

Moderate β€” regular watering

πŸ“… Days to Maturity

60–100 days

πŸ§ͺ Soil pH

Needs 6–7 Β· Your soil: N/A

πŸ—ΊοΈ USDA Zone

Zone 7a

πŸ“† Growing Season

220 days in Seminole County

Growing Tips for Seminole County

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.

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 Seminole County, OK?

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

What planting zone is Seminole County, OK?

Seminole County, Oklahoma is in USDA Hardiness Zone 7a. The average last spring frost is March 31 and first fall frost is November 6.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner β€” designed to help Seminole County gardeners in Zone 7a 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 Seminole County, OK. Local conditions may vary. Last updated: April 2026.