When to Plant Fennel in Hidalgo County, TX
This month in Hidalgo County, Texas
A quick May briefing for Hidalgo County, Texas gardeners — what's urgent, what's next, and what can wait.
-
Start harvesting fennel
If you can't use it all right away, check the food-preservation section of your planner.
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.
Hidalgo County, Texas is in USDA Zone 10a. The average last spring frost is February 6 and the first fall frost is December 18, giving you a growing season of approximately 315 days.
At an elevation of 4,081 feet, Hidalgo County receives approximately 67 inches of rainfall annually with predominantly loam soil. Summer highs average 100°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.
Hidalgo County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
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 Hidalgo County
How your county's soil matches Fennel's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Fennel's range (5.5–7.0), though not a perfect match.
Soil Texture
The loam soil in Hidalgo County is excellent for Fennel — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Fennel.
How to Plant Fennel
Succession Planting Fennel
Sow every 6.9 weeks. Last sowing by Sep 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 | 2.6" | 2.1" | 0.5" | 💧 Light watering |
| Mar | 2.6" | 3.6" | 0" | ✅ Rainfall sufficient |
| Apr | 2.6" | 6.7" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 10.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 9.4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 9.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 8.7" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 6.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.6" | 4.5" | 0" | ✅ Rainfall sufficient |
| Nov | 2.6" | 2.5" | 0.1" | 💧 Light watering |
| Dec | 2.6" | 1.8" | 0.8" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Hidalgo 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 — Hidalgo County, TX
Fennel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 26 | Dec 26 – Jan 9 |
| Transplant Outdoors | February 13 | Feb 13 – Feb 27 |
| Direct Sow | February 6 | Feb 6 – Feb 27 |
| Harvest | April 17 | Apr 17 – May 29 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | — |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | Start Indoors |
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: acceptable
🗺️ USDA Zone
Zone 10a
📆 Growing Season
315 days in Hidalgo County
Growing Tips for Fennel in Hidalgo County
Direct sow Fennel outdoors after February 06 in Hidalgo County when soil has warmed and frost danger has passed.
With summer highs reaching 100°F in Hidalgo 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 Hidalgo County, TX?
Hidalgo County is in Zone 10a with an average last frost of February 6. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hidalgo County, TX?
Hidalgo County, Texas is in USDA Hardiness Zone 10a. The average last spring frost is February 6 and first fall frost is December 18.
Your Hidalgo County Garden Planner — Free
A 24-page printable planner built for Hidalgo County (Zone 10a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.