Blog

When to Plant Celeriac in Brown County, WI

Celeriac is a celery relative grown for its knobby, flavorful root rather than its stalks. It has a rich celery flavor and is excellent roasted, mashed, or in soups.

Brown County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 8 and the first fall frost is October 6, giving you a growing season of approximately 151 days.

At an elevation of 1,235 feet, Brown County receives approximately 34.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Celeriac to ensure they mature before fall.

Brown County, WI (Zone 4b) Moderate season
151 days
Last Spring Frost May 8
151 growing days
First Fall Frost October 6

Brown County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (14 days to spare)
Start indoors: Mar 18 Transplant: Apr 29 🍅 Harvest: Aug 12 – Sep 16
Recommended (50%) ✓ Fits season (11 days to spare)
Start indoors: Mar 27 Transplant: May 8 🍅 Harvest: Aug 21 – Sep 25
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Apr 12 Transplant: May 24 🍅 Harvest: Sep 6 – Oct 11

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
1.5″/week
Rainfall provides
1.0″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 715 gal / 100 sq ft
Celeriac needs ~1,430 GDD — county provides 1,963 GDD Excellent fit

Celeriac Planting Timeline โ€” Brown County, WI

Celeriac Planting Calendar

Activity When Date Range
Start Indoors March 27 Mar 27 โ€“ Apr 10
Transplant Outdoors May 8 May 8 โ€“ May 22
Direct Sow May 1 May 1 โ€“ May 22
Fall Sowing July 14 Jul 14 โ€“ Jul 28
Harvest August 21 Aug 21 โ€“ Sep 25

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors
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

High โ€” keep soil consistently moist

Days to Maturity

100โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 4b

Growing Season

151 days

Growing Tips for Brown County

Start seeds indoors 10-12 weeks before last frost. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Level Up Your Garden

Frequently Asked Questions

When should I plant Celeriac in Brown County, WI?

Brown County is in Zone 4b with an average last frost of May 8. Plan your Celeriac planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Brown County, WI?

Brown County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 8 and first fall frost is October 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Brown County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Brown County, WI. Local conditions may vary. Last updated: April 2026.