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When to Plant Soybeans in Red Lake County, MN

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.

Red Lake County, Minnesota is in USDA Zone 3b. The average last spring frost is May 11 and the first fall frost is October 1, giving you a growing season of approximately 143 days.

At an elevation of 616 feet, Red Lake County receives approximately 36.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Soybeans to ensure they mature before fall.

Red Lake County, MN (Zone 3b) Short season
143 days
Last Spring Frost May 11
143 growing days
First Fall Frost October 1

Red Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (22 days to spare)
Transplant: May 2 🍅 Harvest: Jul 25 – Sep 5
Recommended (50%) ✓ Fits season (17 days to spare)
Transplant: May 11 🍅 Harvest: Aug 3 – Sep 14
Safe Start (90%) ✓ Fits season (19 days to spare)
Transplant: May 22 🍅 Harvest: Aug 14 – 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
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Soybeans needs ~1,000 GDD — county provides 1,430 GDD Excellent fit

Soybeans Planting Timeline โ€” Red Lake County, MN

Soybeans Planting Calendar

Activity When Date Range
Direct Sow May 25 May 25 โ€“ Jun 15
Harvest August 17 Aug 17 โ€“ Sep 28

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Direct Sow
June Direct Sow
July โ€”
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 3b

Growing Season

143 days

Growing Tips for Red Lake 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 Red Lake County, MN?

Red Lake County is in Zone 3b with an average last frost of May 11. Plan your Soybeans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Red Lake County, MN?

Red Lake County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 11 and first fall frost is October 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Red Lake County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.

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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 Red Lake County, MN. Local conditions may vary. Last updated: April 2026.