When to Plant Celeriac in Marathon 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.
Marathon County, Wisconsin is in USDA Zone 4a. The average last spring frost is May 11 and the first fall frost is October 2, giving you a growing season of approximately 144 days.
At an elevation of 723 feet, Marathon County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Celeriac to ensure they mature before fall.
Marathon County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.3
Drainage
Well Drained
Plant Planting Risk Windows
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
Celeriac Planting Timeline — Marathon County, WI
Celeriac Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 30 | Mar 30 – Apr 13 |
| Transplant Outdoors | May 11 | May 11 – May 25 |
| Direct Sow | May 4 | May 4 – May 25 |
| Fall Sowing | July 10 | Jul 10 – Jul 24 |
| Harvest | August 24 | Aug 24 – Sep 28 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
High — keep soil consistently moist
Days to Maturity
100–120 days
Soil pH
6 – 7
USDA Zone
Zone 4a
Growing Season
144 days
Growing Tips for Marathon 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
Level Up Your Garden
Celeriac in Other Locations
Frequently Asked Questions
When should I plant Celeriac in Marathon County, WI?
Marathon County is in Zone 4a with an average last frost of May 11. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marathon County, WI?
Marathon County, Wisconsin is in USDA Hardiness Zone 4a. The average last spring frost is May 11 and first fall frost is October 2.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Marathon County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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