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When to Plant Corn in Laramie County, WY

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.

Laramie County, Wyoming is in USDA Zone 5a. The average last spring frost is May 19 and the first fall frost is September 24, giving you a growing season of approximately 128 days.

At an elevation of 6,153 feet, Laramie County receives approximately 19.3 inches of rainfall annually with predominantly loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Corn to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Corn successfully. Mulch heavily to conserve soil moisture.

Laramie County, WY (Zone 5a) Short season
128 days
Last Spring Frost May 19
128 growing days
First Fall Frost September 24

Laramie County Soil Profile

Soil Type

Loam

Soil pH

6.5-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (9 days to spare)
Transplant: May 12 🍅 Harvest: Jul 14 – Sep 8
Recommended (50%) ✓ Fits season (9 days to spare)
Transplant: May 19 🍅 Harvest: Jul 21 – Sep 15
Safe Start (90%) ✓ Fits season (4 days to spare)
Transplant: Jun 7 🍅 Harvest: Aug 9 – Oct 4

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
0.8″/week
Watering frequency 2-3 times/week
Season total 911 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Corn needs ~980 GDD — county provides 1,568 GDD Excellent fit

Corn Planting Timeline โ€” Laramie County, WY

Corn Planting Calendar

Activity When Date Range
Direct Sow May 26 May 26 โ€“ Jun 16
Harvest July 28 Jul 28 โ€“ Sep 22

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€“100 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5a

Growing Season

128 days

Growing Tips for Laramie 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 Laramie County, WY?

Laramie County is in Zone 5a with an average last frost of May 19. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Laramie County, WY?

Laramie County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 19 and first fall frost is September 24.

๐ŸŒฑ

Plan Your Garden with Confidence

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