When to Plant Fennel in Oconto County, WI
Florence fennel is grown for its swollen bulb-like stem base, which has a mild anise flavor. It is crisp raw in salads and sweet when roasted or braised.
Oconto County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 9 and the first fall frost is October 4, giving you a growing season of approximately 148 days.
At an elevation of 794 feet, Oconto County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Fennel to ensure they mature before fall.
Oconto County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Fennel Planting Timeline — Oconto County, WI
Fennel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | May 30 | May 30 – Jun 13 |
| Direct Sow | May 23 | May 23 – Jun 13 |
| Harvest | August 1 | Aug 1 – Sep 12 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
60–90 days
Soil pH
5.5 – 7
USDA Zone
Zone 4b
Growing Season
148 days
Growing Tips for Oconto County
Direct sow in late summer for fall harvest to reduce bolting. Hill soil around bulbs as they enlarge. Harvest when bulbs are tennis-ball sized before they elongate.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Fennel in Other Locations
Frequently Asked Questions
When should I plant Fennel in Oconto County, WI?
Oconto County is in Zone 4b with an average last frost of May 9. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.
What planting zone is Oconto County, WI?
Oconto County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 9 and first fall frost is October 4.
Plan Your Garden with Confidence
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