When to Plant Soybeans in Warren 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.
Warren County, Illinois is in USDA Zone 5a. The average last spring frost is April 13 and the first fall frost is October 21, giving you a growing season of approximately 191 days.
At an elevation of 801 feet, Warren County receives approximately 36.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Soybeans during the growing season.
Warren County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.8
Drainage
Well Drained
Plant Planting Risk Windows
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Soybeans Planting Timeline — Warren County, IL
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 20 | Apr 20 – May 11 |
| Harvest | July 13 | Jul 13 – Sep 7 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
80–120 days
Soil pH
6 – 7
USDA Zone
Zone 5a
Growing Season
191 days
Growing Tips for Warren 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
Level Up Your Garden
Soybeans in Other Locations
Frequently Asked Questions
When should I plant Soybeans in Warren County, IL?
Warren County is in Zone 5a with an average last frost of April 13. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Warren County, IL?
Warren County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 13 and first fall frost is October 21.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Warren County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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