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When to Plant Corn in Somerset County, ME

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.

Somerset County, Maine is in USDA Zone 4a. The average last spring frost is May 22 and the first fall frost is September 26, giving you a growing season of approximately 127 days.

At an elevation of 356 feet, Somerset County receives approximately 48.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Corn to ensure they mature before fall.

Somerset County, ME (Zone 4a) Short season
127 days
Last Spring Frost May 22
127 growing days
First Fall Frost September 26

Somerset County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (8 days to spare)
Transplant: May 15 🍅 Harvest: Jul 17 – Sep 11
Recommended (50%) ✓ Fits season (8 days to spare)
Transplant: May 22 🍅 Harvest: Jul 24 – Sep 18
Safe Start (90%) ✓ Fits season (11 days to spare)
Transplant: Jun 3 🍅 Harvest: Aug 5 – Sep 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
1.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Corn needs ~800 GDD — county provides 1,270 GDD Excellent fit

Corn Planting Timeline โ€” Somerset County, ME

Corn Planting Calendar

Activity When Date Range
Direct Sow June 5 Jun 5 โ€“ Jun 26
Harvest August 7 Aug 7 โ€“ Oct 2

Plant 1" deep ยท 12" apart ยท Rows 36" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May โ€”
June Direct Sow
July โ€”
August Harvest
September Harvest
October Harvest
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 4a

Growing Season

127 days

Growing Tips for Somerset 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 Somerset County, ME?

Somerset County is in Zone 4a with an average last frost of May 22. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Somerset County, ME?

Somerset County, Maine is in USDA Hardiness Zone 4a. The average last spring frost is May 22 and first fall frost is September 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Somerset County gardeners in Zone 4a 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 Somerset County, ME. Local conditions may vary. Last updated: April 2026.