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When to Plant Soybeans in Logan County, CO

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.

Logan County, Colorado is in USDA Zone 5a. The average last spring frost is May 11 and the first fall frost is October 5, giving you a growing season of approximately 147 days.

At an elevation of 6,511 feet, Logan County receives approximately 14.9 inches of rainfall annually with predominantly loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Soybeans to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Soybeans successfully. Mulch heavily to conserve soil moisture.

Logan County, CO (Zone 5a) Short season
147 days
Last Spring Frost May 11
147 growing days
First Fall Frost October 5

Logan County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (13 days to spare)
Transplant: May 2 🍅 Harvest: Jul 25 – Sep 19
Recommended (50%) ✓ Fits season (7 days to spare)
Transplant: May 11 🍅 Harvest: Aug 3 – Sep 28
Safe Start (90%) ✓ Fits season (7 days to spare)
Transplant: May 21 🍅 Harvest: Aug 13 – Oct 8

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
0.4″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 902 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Soybeans needs ~1,225 GDD — county provides 1,800 GDD Excellent fit

Soybeans Planting Timeline โ€” Logan County, CO

Soybeans Planting Calendar

Activity When Date Range
Direct Sow May 18 May 18 โ€“ Jun 8
Harvest August 10 Aug 10 โ€“ Oct 5

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 5a

Growing Season

147 days

Growing Tips for Logan 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 Logan County, CO?

Logan County is in Zone 5a 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 Logan County, CO?

Logan County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is May 11 and first fall frost is October 5.

๐ŸŒฑ

Plan Your Garden with Confidence

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