When to Plant Fennel in Bexar County, TX
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.
Bexar County, Texas is in USDA Zone 8b. The average last spring frost is March 11 and the first fall frost is November 17, giving you a growing season of approximately 251 days.
At an elevation of 3,197 feet, Bexar County receives approximately 52.1 inches of rainfall annually with predominantly loam soil. Summer highs average 93°F, providing good warmth for Fennel during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Fennel root diseases.
Bexar County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
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.
Soil Compatibility in Bexar County
How your county's soil matches Fennel's growing requirements.
Soil pH
Your soil pH (6.5–7.8) is more alkaline than Fennel prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Bexar County is excellent for Fennel — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Fennel.
How to Plant Fennel
Succession Planting Fennel
Sow every 6.9 weeks. Last sowing by Aug 19 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Fennel
Fennel needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.
| Month | Fennel Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | 2.6" | 3.6" | 0" | ✅ Rainfall sufficient |
| Apr | 2.6" | 5.6" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 7.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 8.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 6.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 6.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 4.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.6" | 3.5" | 0" | ✅ Rainfall sufficient |
| Nov | 2.6" | 1.9" | 0.7" | 💧 Light watering |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Bexar County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Fennel Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Fennel Planting Timeline — Bexar County, TX
Fennel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 21 | Jan 21 – Feb 4 |
| Transplant Outdoors | March 25 | Mar 25 – Apr 8 |
| Direct Sow | March 18 | Mar 18 – Apr 8 |
| Harvest | May 27 | May 27 – Jul 8 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.6"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 8b
📆 Growing Season
251 days in Bexar County
Growing Tips for Fennel in Bexar County
Direct sow Fennel outdoors after March 11 in Bexar County when soil has warmed and frost danger has passed.
Common pests for Fennel in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
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
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Fennel in Other Locations
Frequently Asked Questions
When should I plant Fennel in Bexar County, TX?
Bexar County is in Zone 8b with an average last frost of March 11. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.
What planting zone is Bexar County, TX?
Bexar County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 11 and first fall frost is November 17.
Plan Your Garden with Confidence
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