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When to Plant Corn in Miller County, MO

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.

Miller County, Missouri is in USDA Zone 6a. The average last spring frost is April 6 and the first fall frost is October 27, giving you a growing season of approximately 204 days.

At an elevation of 1,086 feet, Miller County receives approximately 30.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Corn during the growing season.

Miller County, MO (Zone 6a) Long season
204 days
Last Spring Frost April 6
204 growing days
First Fall Frost October 27

Miller County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (84 days to spare)
Transplant: Mar 31 🍅 Harvest: Jun 2 – Jul 28
Recommended (50%) ✓ Fits season (85 days to spare)
Transplant: Apr 6 🍅 Harvest: Jun 8 – Aug 3
Safe Start (90%) ✓ Fits season (85 days to spare)
Transplant: Apr 21 🍅 Harvest: Jun 23 – Aug 18

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
0.6″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 120 gal / 100 sq ft
Corn needs ~1,340 GDD — county provides 3,417 GDD Excellent fit

Corn Planting Timeline โ€” Miller County, MO

Corn Planting Calendar

Activity When Date Range
Direct Sow April 13 Apr 13 โ€“ May 4
Harvest June 15 Jun 15 โ€“ Aug 10

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 6a

Growing Season

204 days

Growing Tips for Miller 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 Miller County, MO?

Miller County is in Zone 6a with an average last frost of April 6. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Miller County, MO?

Miller County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 6 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Miller County gardeners in Zone 6a 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 Miller County, MO. Local conditions may vary. Last updated: April 2026.