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When to Plant Onion in Pope County, MN

Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.

Pope County, Minnesota is in USDA Zone 4a. The average last spring frost is May 4 and the first fall frost is October 3, giving you a growing season of approximately 152 days.

At an elevation of 1,061 feet, Pope County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Onion to ensure they mature before fall.

Pope County, MN (Zone 4a) Moderate season
152 days
Last Spring Frost May 4
152 growing days
First Fall Frost October 3

Pope County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (12 days to spare)
Start indoors: Mar 16 Transplant: Apr 27 🍅 Harvest: Jul 27 – Sep 14
Recommended (50%) ✓ Fits season (12 days to spare)
Start indoors: Mar 23 Transplant: May 4 🍅 Harvest: Aug 3 – Sep 21
Safe Start (90%) ✓ Fits season (10 days to spare)
Start indoors: Apr 5 Transplant: May 17 🍅 Harvest: Aug 16 – Oct 4

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
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 228 gal / 100 sq ft
Drought risk

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

Onion needs ~1,365 GDD — county provides 1,976 GDD Excellent fit

Onion Planting Timeline โ€” Pope County, MN

Onion Planting Calendar

Activity When Date Range
Start Indoors March 23 Mar 23 โ€“ Apr 6
Transplant Outdoors May 4 May 4 โ€“ May 18
Direct Sow April 27 Apr 27 โ€“ May 18
Fall Sowing July 11 Jul 11 โ€“ Jul 25
Harvest August 3 Aug 3 โ€“ Sep 21

Plant 1" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July Fall Sowing
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

90โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 4a

Growing Season

152 days

Growing Tips for Pope County

Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans
  • Asparagus

Level Up Your Garden

Frequently Asked Questions

When should I plant Onion in Pope County, MN?

Pope County is in Zone 4a with an average last frost of May 4. Plan your Onion planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pope County, MN?

Pope County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 4 and first fall frost is October 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pope County gardeners in Zone 4a 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 Pope County, MN. Local conditions may vary. Last updated: April 2026.