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When to Plant Soybeans in Clearwater 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.

Clearwater County, Minnesota is in USDA Zone 3b. The average last spring frost is May 15 and the first fall frost is September 28, giving you a growing season of approximately 136 days.

At an elevation of 1,074 feet, Clearwater County receives approximately 33.7 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.

Clearwater County, MN (Zone 3b) Short season
136 days
Last Spring Frost May 15
136 growing days
First Fall Frost September 28

Clearwater County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (10 days to spare)
Transplant: May 8 🍅 Harvest: Jul 31 – Sep 11
Recommended (50%) ✓ Fits season (10 days to spare)
Transplant: May 15 🍅 Harvest: Aug 7 – Sep 18
Safe Start (90%) ✓ Fits season (12 days to spare)
Transplant: May 28 🍅 Harvest: Aug 20 – Oct 1

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
1.0″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 377 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Soybeans needs ~1,000 GDD — county provides 1,360 GDD Excellent fit

Soybeans Planting Timeline โ€” Clearwater County, MN

Soybeans Planting Calendar

Activity When Date Range
Direct Sow May 29 May 29 โ€“ Jun 19
Harvest August 21 Aug 21 โ€“ Oct 2

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 Harvest
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

136 days

Growing Tips for Clearwater 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 Clearwater County, MN?

Clearwater County is in Zone 3b with an average last frost of May 15. Plan your Soybeans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clearwater County, MN?

Clearwater County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 15 and first fall frost is September 28.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clearwater 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 Clearwater County, MN. Local conditions may vary. Last updated: April 2026.