Blog

When to Plant Soybeans in Peoria County, IL

Soybeans (edamame) are a high-protein legume that fixes nitrogen in the soil. Fresh green soybeans harvested at the edamame stage are a nutritious snack.

Peoria County, Illinois is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 12, giving you a growing season of approximately 172 days.

At an elevation of 884 feet, Peoria County receives approximately 33 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Soybeans during the growing season.

Peoria County, IL (Zone 5b) Moderate season
172 days
Last Spring Frost April 23
172 growing days
First Fall Frost October 12

Peoria County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Transplant: Apr 17 🍅 Harvest: Jul 10 – Sep 4
Recommended (50%) ✓ Fits season (32 days to spare)
Transplant: Apr 23 🍅 Harvest: Jul 16 – Sep 10
Safe Start (90%) ✓ Fits season (33 days to spare)
Transplant: May 8 🍅 Harvest: Jul 31 – Sep 25

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
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 297 gal / 100 sq ft
Soybeans needs ~1,450 GDD — county provides 2,494 GDD Excellent fit

Soybeans Planting Timeline โ€” Peoria County, IL

Soybeans Planting Calendar

Activity When Date Range
Direct Sow April 30 Apr 30 โ€“ May 21
Harvest July 23 Jul 23 โ€“ Sep 17

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Direct Sow
May Direct Sow
June โ€”
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

80โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

172 days

Growing Tips for Peoria County

Direct sow after soil warms to 60F. Plant in blocks rather than rows for better pollination. Harvest for edamame when pods are plump and bright green.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Level Up Your Garden

Frequently Asked Questions

When should I plant Soybeans in Peoria County, IL?

Peoria County is in Zone 5b with an average last frost of April 23. Plan your Soybeans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Peoria County, IL?

Peoria County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 12.

๐ŸŒฑ

Plan Your Garden with Confidence

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