When to Plant Fennel in Thurston County, WA
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.
Thurston County, Washington is in USDA Zone 8a. The average last spring frost is April 15 and the first fall frost is October 29, giving you a growing season of approximately 197 days.
At an elevation of 213 feet, Thurston County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Fennel during the growing season.
Thurston County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.6
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 Planting Timeline — Thurston County, WA
Fennel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 25 | Feb 25 – Mar 11 |
| Transplant Outdoors | April 29 | Apr 29 – May 13 |
| Direct Sow | April 22 | Apr 22 – May 13 |
| Harvest | July 1 | Jul 1 – Aug 12 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| 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 8a
Growing Season
197 days
Growing Tips for Thurston 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 Thurston County, WA?
Thurston County is in Zone 8a with an average last frost of April 15. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.
What planting zone is Thurston County, WA?
Thurston County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 15 and first fall frost is October 29.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Thurston County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.
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