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When to Plant Daikon in Polk County, WI

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.

Polk County, Wisconsin is in USDA Zone 4a. The average last spring frost is May 12 and the first fall frost is September 29, giving you a growing season of approximately 140 days.

At an elevation of 582 feet, Polk County receives approximately 40 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82ยฐF, so choose short-season varieties of Daikon to ensure they mature before fall.

Polk County, WI (Zone 4a) Short season
140 days
Last Spring Frost May 12
140 growing days
First Fall Frost September 29

Polk County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (63 days to spare)
Transplant: Apr 30 🍅 Harvest: Jun 25 – Jul 23
Recommended (50%) ✓ Fits season (56 days to spare)
Transplant: May 12 🍅 Harvest: Jul 7 – Aug 4
Safe Start (90%) ✓ Fits season (62 days to spare)
Transplant: May 20 🍅 Harvest: Jul 15 – Aug 12

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
1.2″/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

Daikon needs ~690 GDD — county provides 1,610 GDD Excellent fit

Daikon Planting Timeline โ€” Polk County, WI

Daikon Planting Calendar

Activity When Date Range
Direct Sow May 5 May 5 โ€“ May 26
Fall Sowing July 7 Jul 7 โ€“ Jul 21
Harvest June 30 Jun 30 โ€“ Jul 28

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 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

50โ€“70 days

Soil pH

5.8 โ€“ 7

USDA Zone

Zone 4a

Growing Season

140 days

Growing Tips for Polk 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 Polk County, WI?

Polk County is in Zone 4a with an average last frost of May 12. Plan your Daikon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Polk County, WI?

Polk County, Wisconsin is in USDA Hardiness Zone 4a. The average last spring frost is May 12 and first fall frost is September 29.

๐ŸŒฑ

Plan Your Garden with Confidence

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