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When to Plant Daikon in St. Louis County, MN

Daikon is a large, mild Japanese radish that can grow over a foot long. It is excellent for pickling, stir-fries, and as a soil-breaking cover crop.

St. Louis County, Minnesota is in USDA Zone 3a. The average last spring frost is June 2 and the first fall frost is September 10, giving you a growing season of approximately 100 days.

At an elevation of 531 feet, St. Louis County receives approximately 36.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 78ยฐF, so choose short-season varieties of Daikon to ensure they mature before fall.

St. Louis County, MN (Zone 3a) Short season
100 days
Last Spring Frost June 2
100 growing days
First Fall Frost September 10

St. Louis County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (16 days to spare)
Transplant: May 28 🍅 Harvest: Jul 23 – Aug 20
Recommended (50%) ✓ Fits season (16 days to spare)
Transplant: Jun 2 🍅 Harvest: Jul 28 – Aug 25
Safe Start (90%) ✓ Fits season (14 days to spare)
Transplant: Jun 16 🍅 Harvest: Aug 11 – Sep 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
1.5″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Daikon needs ~510 GDD — county provides 850 GDD Excellent fit

Daikon Planting Timeline โ€” St. Louis County, MN

Daikon Planting Calendar

Activity When Date Range
Direct Sow May 26 May 26 โ€“ Jun 16
Fall Sowing June 18 Jun 18 โ€“ Jul 2
Harvest July 21 Jul 21 โ€“ Aug 18

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“70 days

Soil pH

5.8 โ€“ 7

USDA Zone

Zone 3a

Growing Season

100 days

Growing Tips for St. Louis County

Direct sow in late summer for fall harvest. Loosen soil deeply before planting. Thin seedlings to 6 inches apart. Harvest before hard freeze as exposed shoulders may crack.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Level Up Your Garden

Frequently Asked Questions

When should I plant Daikon in St. Louis County, MN?

St. Louis County is in Zone 3a with an average last frost of June 2. Plan your Daikon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is St. Louis County, MN?

St. Louis County, Minnesota is in USDA Hardiness Zone 3a. The average last spring frost is June 2 and first fall frost is September 10.

๐ŸŒฑ

Plan Your Garden with Confidence

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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 St. Louis County, MN. Local conditions may vary. Last updated: April 2026.