When to Plant Fennel (herb) in Oneida County, WI
Herb fennel is grown for its aromatic leaves, stalks, and seeds rather than a bulb. It has a strong anise flavor and its flowers attract beneficial insects.
Oneida County, Wisconsin is in USDA Zone 4a. The average last spring frost is May 20 and the first fall frost is September 28, giving you a growing season of approximately 131 days.
At an elevation of 569 feet, Oneida County receives approximately 39.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Fennel (herb) to ensure they mature before fall.
Oneida County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-7.1
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
Fennel (herb) Planting Timeline — Oneida County, WI
Fennel (herb) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 8 | Apr 8 – Apr 22 |
| Transplant Outdoors | May 13 | May 13 – May 27 |
| Direct Sow | May 13 | May 13 – Jun 3 |
| Fall Sowing | July 6 | Jul 6 – Jul 20 |
| Harvest | July 15 | Jul 15 – Sep 23 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Direct Sow |
| July | Fall Sowing Harvest |
| 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 4a
Growing Season
131 days
Growing Tips for Oneida County
Direct sow in spring or fall. Unlike Florence fennel, herb fennel does not form a bulb. Harvest fronds as needed and seeds when they turn brown. Self-sows readily.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Fennel (herb) in Other Locations
Frequently Asked Questions
When should I plant Fennel (herb) in Oneida County, WI?
Oneida County is in Zone 4a with an average last frost of May 20. Plan your Fennel (herb) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Oneida County, WI?
Oneida County, Wisconsin is in USDA Hardiness Zone 4a. The average last spring frost is May 20 and first fall frost is September 28.
Plan Your Garden with Confidence
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