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When to Plant Radish in Roseau County, MN

Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

Roseau County, Minnesota is in USDA Zone 3a. The average last spring frost is May 21 and the first fall frost is September 22, giving you a growing season of approximately 124 days.

At an elevation of 655 feet, Roseau County receives approximately 32 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79ยฐF, so choose short-season varieties of Radish to ensure they mature before fall.

Roseau County, MN (Zone 3a) Short season
124 days
Last Spring Frost May 21
124 growing days
First Fall Frost September 22

Roseau County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (77 days to spare)
Transplant: May 11 🍅 Harvest: Jun 8 – Jun 29
Recommended (50%) ✓ Fits season (75 days to spare)
Transplant: May 21 🍅 Harvest: Jun 18 – Jul 9
Safe Start (90%) ✓ Fits season (77 days to spare)
Transplant: Jun 4 🍅 Harvest: Jul 2 – Jul 23

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
Drought risk

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

Radish needs ~264 GDD — county provides 1,147 GDD Excellent fit

Radish Planting Timeline โ€” Roseau County, MN

Radish Planting Calendar

Activity When Date Range
Direct Sow May 14 May 14 โ€“ Jun 4
Fall Sowing June 30 Jun 30 โ€“ Jul 14
Harvest June 11 Jun 11 โ€“ Jul 2

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Direct Sow
June Direct Sow Fall Sowing Harvest
July Fall Sowing Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

22โ€“35 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 3a

Growing Season

124 days

Growing Tips for Roseau County

Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Level Up Your Garden

Frequently Asked Questions

When should I plant Radish in Roseau County, MN?

Roseau County is in Zone 3a with an average last frost of May 21. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Roseau County, MN?

Roseau County, Minnesota is in USDA Hardiness Zone 3a. The average last spring frost is May 21 and first fall frost is September 22.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Roseau County gardeners in Zone 3a 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 Roseau County, MN. Local conditions may vary. Last updated: April 2026.