When to Plant Basil in Starr County, TX
Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.
Starr County, Texas is in USDA Zone 9b. The average last spring frost is February 3 and the first fall frost is December 16, giving you a growing season of approximately 316 days.
At an elevation of 2,451 feet, Starr County receives approximately 55.4 inches of rainfall annually with predominantly loam soil. Summer highs average 98°F, so Basil may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Basil root diseases.
Starr County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.5
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 Starr County
How your county's soil matches Basil's growing requirements.
Soil pH
Your soil pH (6.8–7.5) is more alkaline than Basil prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Starr County is excellent for Basil — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Basil.
How to Plant Basil
Succession Planting Basil
Sow every 5.7 weeks. Last sowing by Oct 02 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Basil
Basil 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 | Basil Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 2.6" | 1.9" | 0.7" | 💧 Light watering |
| Mar | 2.6" | 3.4" | 0" | ✅ Rainfall sufficient |
| Apr | 2.6" | 6.6" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 8.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 7.6" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 7" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 6.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 4.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.6" | 4" | 0" | ✅ Rainfall sufficient |
| Nov | 2.6" | 1.6" | 1" | 💧 Light watering |
| Dec | 2.6" | 1.6" | 1" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Starr County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Basil 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.
Basil Planting Timeline — Starr County, TX
Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 23 | Dec 23 – Jan 6 |
| Transplant Outdoors | February 10 | Feb 10 – Feb 24 |
| Direct Sow | February 10 | Feb 10 – Mar 3 |
| Harvest | April 7 | Apr 7 – Jun 9 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Direct Sow |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| 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
50–75 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 9b
📆 Growing Season
316 days in Starr County
Growing Tips for Basil in Starr County
Direct sow Basil outdoors after February 03 in Starr County when soil has warmed and frost danger has passed.
With summer highs reaching 98°F in Starr County, provide afternoon shade for Basil and water deeply in the morning.
General growing tips
Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.
Recommended Basil Varieties for Starr County
Downy mildew-resistant basil for your humid climate
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 150 ft between varieties. Different basil species can cross.
Basil in Other Locations
Frequently Asked Questions
When should I plant Basil in Starr County, TX?
Starr County is in Zone 9b with an average last frost of February 3. Plan your Basil planting based on this frost date — see the calendar above for exact timing.
What planting zone is Starr County, TX?
Starr County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 3 and first fall frost is December 16.
Plan Your Garden with Confidence
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