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When to plant Sweet Corn in Fremont County, CO

Plant Sweet Corn in Fremont County, between May 30 and June 20 — the only viable window. Zone 6a's short season (125 frost-free days) rules out a fall crop.

When to Plant Sweet Corn in Fremont County, CO

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.

Fremont County, Colorado is in USDA Zone 6a. The average last spring frost is May 23 and the first fall frost is September 25, giving you a growing season of approximately 125 days.

At an elevation of 6,575 feet, Fremont County receives approximately 18.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Sweet Corn to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Sweet Corn successfully. Mulch heavily to conserve soil moisture.

Fremont County, CO (Zone 6a) Short season
125 days
Last Spring Frost May 23
125 growing days
First Fall Frost September 25

Fremont County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Sweet Corn Planting Timeline — Fremont County, CO

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow May 30 May 30 – Jun 20
Harvest August 1 Aug 1 – Sep 12

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

125 days in Fremont County

Growing Tips for Fremont 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Corn in Fremont County, CO?

Fremont County is in Zone 6a with an average last frost of May 23. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Fremont County, CO?

Fremont County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is May 23 and first fall frost is September 25.

When should I plant Sweet Corn in Fremont County, CO?

In Fremont County, CO, plant Sweet Corn after the last frost (around May 23) and before the first frost (around September 25). Best results when soil holds above 50°F.

What growing zone is Fremont County, CO for Sweet Corn?

Fremont County sits in USDA Zone 6a. Sweet Corn grows reliably in zones 3a through 11b, so it's a good fit here.

Can Sweet Corn grow in Fremont County's climate?

Yes — Sweet Corn grows well in Fremont County's temperate climate. Fremont County averages a 125-day frost-free season, with last frost around May 23 and first frost around September 25.

🌱

Your Fremont County Garden Planner — Free

A 22-page printable planner built for Fremont County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Fremont County, CO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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