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When to Plant Corn in Appanoose County, IA

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.

Appanoose County, Iowa is in USDA Zone 5b. The average last spring frost is April 20 and the first fall frost is October 16, giving you a growing season of approximately 179 days.

At an elevation of 640 feet, Appanoose County receives approximately 33.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Corn during the growing season.

Appanoose County, IA (Zone 5b) Moderate season
179 days
Last Spring Frost April 20
179 growing days
First Fall Frost October 16

Appanoose County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (60 days to spare)
Transplant: Apr 14 🍅 Harvest: Jun 16 – Aug 11
Recommended (50%) ✓ Fits season (60 days to spare)
Transplant: Apr 20 🍅 Harvest: Jun 22 – Aug 17
Safe Start (90%) ✓ Fits season (61 days to spare)
Transplant: May 3 🍅 Harvest: Jul 5 – Aug 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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 356 gal / 100 sq ft
Corn needs ~1,220 GDD — county provides 2,729 GDD Excellent fit

Corn Planting Timeline โ€” Appanoose County, IA

Corn Planting Calendar

Activity When Date Range
Direct Sow April 27 Apr 27 โ€“ May 18
Harvest June 29 Jun 29 โ€“ Aug 24

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 Direct Sow
June Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“100 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

179 days

Growing Tips for Appanoose 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

Level Up Your Garden

Frequently Asked Questions

When should I plant Corn in Appanoose County, IA?

Appanoose County is in Zone 5b with an average last frost of April 20. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Appanoose County, IA?

Appanoose County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 20 and first fall frost is October 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Appanoose County gardeners in Zone 5b 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 Appanoose County, IA. Local conditions may vary. Last updated: April 2026.