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When to plant Corn in Champaign County, IL

For Champaign County, gardeners: plant Corn April 21 through May 12 once soil reads 50°F.

When to Plant Corn in Champaign County, IL

Corn

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.

Champaign County, Illinois is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 19, giving you a growing season of approximately 188 days.

At an elevation of 1,215 feet, Champaign County receives approximately 38.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Corn during the growing season.

Champaign County, IL (Zone 6a) Moderate season
188 days
Last Spring Frost April 14
188 growing days
First Fall Frost October 19

Champaign County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

How Much Corn to Grow

1-2 ears
Average yield per plant
15
Plants per person
30 sq ft
Space per person

For a family of 4, plant approximately 60 corn plants in about 120 sq ft. In Champaign County's 188-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Corn

Corn needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Corn Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 4" 0.3" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Champaign County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Corn Planting Timeline — Champaign County, IL

Corn Planting Calendar

Activity When Date Range
Direct Sow April 21 Apr 21 – May 12
Harvest June 23 Jun 23 – Aug 18

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

60–100 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

188 days in Champaign County

Growing Tips for Champaign 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in Champaign County, IL?

Champaign County is in Zone 6a with an average last frost of April 14. Plan your Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Champaign County, IL?

Champaign County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 19.

When should I plant Corn in Champaign County, IL?

In Champaign County, IL, plant Corn after the last frost (around April 14) and before the first frost (around October 19). Best results when soil holds above 50°F.

What growing zone is Champaign County, IL for Corn?

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

Can Corn grow in Champaign County's climate?

Yes — Corn grows well in Champaign County's temperate climate. Champaign County averages a 188-day frost-free season, with last frost around April 14 and first frost around October 19.

🌱

Your Champaign County Garden Planner — Free

A 22-page printable planner built for Champaign 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Champaign County, IL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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