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When to Plant Sweet Corn in Windham County, VT

Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.

Windham County, Vermont is in USDA Zone 5a. The average last spring frost is May 12 and the first fall frost is October 7, giving you a growing season of approximately 148 days.

At an elevation of 1,164 feet, Windham County receives approximately 49.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Sweet Corn during the growing season.

Windham County, VT (Zone 5a) Short season
148 days
Last Spring Frost May 12
148 growing days
First Fall Frost October 7

Windham County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (45 days to spare)
Transplant: May 7 🍅 Harvest: Jul 9 – Aug 20
Recommended (50%) ✓ Fits season (43 days to spare)
Transplant: May 12 🍅 Harvest: Jul 14 – Aug 25
Safe Start (90%) ✓ Fits season (43 days to spare)
Transplant: May 26 🍅 Harvest: Jul 28 – Sep 8

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
1.4″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Sweet Corn needs ~1,088 GDD — county provides 2,146 GDD Excellent fit

Sweet Corn Planting Timeline โ€” Windham County, VT

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow May 19 May 19 โ€“ Jun 9
Harvest July 21 Jul 21 โ€“ Sep 1

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“90 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5a

Growing Season

148 days

Growing Tips for Windham County

Plant in blocks of at least 4 rows for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Sweet Corn in Windham County, VT?

Windham County is in Zone 5a with an average last frost of May 12. Plan your Sweet Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Windham County, VT?

Windham County, Vermont is in USDA Hardiness Zone 5a. The average last spring frost is May 12 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

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