When to Plant Thai Basil in King County, TX
Thai basil has a distinctive anise-licorice flavor with sturdy purple stems and small leaves. It is essential in Thai, Vietnamese, and other Southeast Asian cuisines.
King County, Texas is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.
At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Thai Basil may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Thai Basil will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Thai Basil root diseases.
King County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.8-8.4
Drainage
Well Drained
Monthly Watering Guide for Thai Basil
Thai Basil needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Thai Basil Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.7" | 0" | ❄️ Dormant |
| Feb | — | 3.2" | 0" | ❄️ Dormant |
| Mar | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Apr | 4.3" | 2.3" | 2" | 💧 Light watering |
| May | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jun | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Jul | 4.3" | 10.4" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 11.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 8.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 3" | 1.3" | 💧 Light watering |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in King County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Thai Basil Planting Timeline — King County, TX
Thai Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 10 | Feb 10 – Feb 24 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | April 7 | Apr 7 – Apr 28 |
| Harvest | June 9 | Jun 9 – Aug 11 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
50–75 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 7b
📆 Growing Season
221 days in King County
Growing Tips for King County
Start seeds indoors or direct sow after last frost. Thai basil holds up better to heat in cooking than sweet basil. Pinch flowers to prolong leaf production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Thai Basil in Other Locations
Frequently Asked Questions
When should I plant Thai Basil in King County, TX?
King County is in Zone 7b with an average last frost of March 31. Plan your Thai Basil planting based on this frost date — see the calendar above for exact timing.
What planting zone is King County, TX?
King County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 7.
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