When to Plant Fennel in Duval 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.
Duval County, Texas is in USDA Zone 9a. The average last spring frost is February 13 and the first fall frost is December 9, giving you a growing season of approximately 299 days.
At an elevation of 4,259 feet, Duval County receives approximately 55.2 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Fennel may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Fennel root diseases.
Duval County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.3
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.
Soil Compatibility in Duval County
How your county's soil matches Fennel's growing requirements.
Soil pH
Your soil pH (6.8–7.3) is more alkaline than Fennel prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Duval County is excellent for Fennel — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Fennel.
How to Plant Fennel
Succession Planting Fennel
Sow every 6.9 weeks. Last sowing by Sep 10 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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 2.6" | 1.7" | 0.9" | 💧 Light watering |
| Mar | 2.6" | 4" | 0" | ✅ Rainfall sufficient |
| Apr | 2.6" | 5.3" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 8.7" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 8.4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 6.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 6" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 5.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.6" | 3.6" | 0" | ✅ Rainfall sufficient |
| Nov | 2.6" | 1.9" | 0.7" | 💧 Light watering |
| Dec | 2.6" | 1.6" | 1" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Duval 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 — Duval County, TX
Fennel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 2 | Jan 2 – Jan 16 |
| Transplant Outdoors | February 20 | Feb 20 – Mar 6 |
| Direct Sow | February 13 | Feb 13 – Mar 6 |
| Harvest | April 24 | Apr 24 – Jun 5 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| 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 9a
📆 Growing Season
299 days in Duval County
Growing Tips for Fennel in Duval County
Direct sow Fennel outdoors after February 13 in Duval County when soil has warmed and frost danger has passed.
With summer highs reaching 102°F in Duval County, provide afternoon shade for Fennel and water deeply in the morning.
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
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Fennel in Other Locations
Frequently Asked Questions
When should I plant Fennel in Duval County, TX?
Duval County is in Zone 9a with an average last frost of February 13. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.
What planting zone is Duval County, TX?
Duval County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 13 and first fall frost is December 9.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Duval County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.