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When to plant Sweet Corn in Lee County, IA

Spring Sweet Corn in Lee County goes in April 23–May 14, once nighttime temps stop dipping near freezing.

When to Plant Sweet Corn in Lee County, IA

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.

Lee County, Iowa is in USDA Zone 6a. The average last spring frost is April 16 and the first fall frost is October 18, giving you a growing season of approximately 185 days.

At an elevation of 1,393 feet, Lee County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Sweet Corn to ensure they mature before fall.

Lee County, IA (Zone 6a) Moderate season
185 days
Last Spring Frost April 16
185 growing days
First Fall Frost October 18

Lee County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Sweet Corn Planting Timeline — Lee County, IA

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow April 23 Apr 23 – May 14
Harvest June 25 Jun 25 – Aug 6

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

Month-by-Month Timeline

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

185 days in Lee County

Growing Tips for Lee 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 Lee County, IA?

Lee County is in Zone 6a with an average last frost of April 16. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lee County, IA?

Lee County, Iowa is in USDA Hardiness Zone 6a. The average last spring frost is April 16 and first fall frost is October 18.

When should I plant Sweet Corn in Lee County, IA?

In Lee County, IA, plant Sweet Corn after the last frost (around April 16) and before the first frost (around October 18). Best results when soil holds above 50°F.

What growing zone is Lee County, IA for Sweet Corn?

Lee 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 Lee County's climate?

Yes — Sweet Corn grows well in Lee County's temperate climate. Lee County averages a 185-day frost-free season, with last frost around April 16 and first frost around October 18.

🌱

Your Lee County Garden Planner — Free

A 22-page printable planner built for Lee 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 Lee County, IA. Local conditions may vary. Last updated: July 2026.

Sources & credits

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