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When to plant Soybeans in Alexander County County,

Alexander County County's spring Soybeans window runs April 17 through May 8. most warm-season crops establish quickly once soil holds above 60°F.

When to Plant Soybeans in Alexander 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.

Alexander County, Illinois is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 21, giving you a growing season of approximately 194 days.

At an elevation of 1,260 feet, Alexander County receives approximately 38.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Soybeans during the growing season.

Alexander County, IL (Zone 7a) Moderate season
194 days
Last Spring Frost April 10
194 growing days
First Fall Frost October 21
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Alexander County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7

Drainage

Well Drained

Monthly Watering Guide for Soybeans

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

Month Soybeans Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 3" 0" ❄️ Dormant
Apr 4.3" 4.3" 0" ✅ Rainfall sufficient
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 5.1" 0" ✅ Rainfall sufficient
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 4.8" 0" ✅ Rainfall sufficient
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

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

Soybeans Planting Timeline — Alexander County, IL

Soybeans Planting Calendar

Activity When Date Range
Direct Sow April 17 Apr 17 – May 8
Harvest July 10 Jul 10 – Sep 4

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

194 days in Alexander County

Growing Tips for Alexander 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Soybeans in Alexander County, IL?

Alexander County is in Zone 7a with an average last frost of April 10. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Alexander County, IL?

Alexander County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 21.

When should I plant Soybeans in Alexander County County, ?

In Alexander County County, , plant Soybeans after the last frost (around April 10) and before the first frost (around October 21). Best results when soil holds above 50°F.

What growing zone is Alexander County County, for Soybeans?

Alexander County County sits in USDA Zone 7a. Soybeans grows reliably in zones 3a through 10b, so it's a good fit here.

Can Soybeans grow in Alexander County County's climate?

Yes — Soybeans grows well in Alexander County County's temperate climate. Alexander County County averages a 194-day frost-free season, with last frost around April 10 and first frost around October 21.

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Your Alexander County Garden Planner — Free

A 22-page printable planner built for Alexander County (Zone 7a). 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 Alexander County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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