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When to Plant Thai Basil in Upton 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.

Upton County, Texas is in USDA Zone 7b. The average last spring frost is March 20 and the first fall frost is November 12, giving you a growing season of approximately 237 days.

At an elevation of 1,734 feet, Upton County receives approximately 50.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96ยฐF, so Thai Basil may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” 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.

Upton County, TX (Zone 7b) Long season
237 days
Last Spring Frost March 20
237 growing days
First Fall Frost November 12

Upton County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (105 days to spare)
Start indoors: Jan 20 Transplant: Mar 24 🍅 Harvest: May 19 – Jul 21
Recommended (50%) ✓ Fits season (104 days to spare)
Start indoors: Jan 30 Transplant: Apr 3 🍅 Harvest: May 29 – Jul 31
Safe Start (90%) ✓ Fits season (97 days to spare)
Start indoors: Feb 23 Transplant: Apr 27 🍅 Harvest: Jun 22 – Aug 24

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 Upton County

How your county's soil matches Thai Basil's growing requirements.

Soil pH

Your soil pH (7.8โ€“8.3) is more alkaline than Thai Basil prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Upton County warms quickly in spring but drains fast. Thai Basil will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.0%). Add 2-3 inches of compost before planting Thai Basil.

How to Plant Thai Basil

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Thai Basil

5
successive plantings in your 237-day season

Sow every 5.7 weeks. Last sowing by Aug 29 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 248 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

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 โ€” 3.9" 0" โ„๏ธ Dormant
Feb โ€” 2.5" 0" โ„๏ธ Dormant
Mar 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Apr 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
May 4.3" 1.3" 3" ๐Ÿšฟ Regular watering
Jun 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Jul 4.3" 8.4" 0" โœ… Rainfall sufficient
Aug 4.3" 9.8" 0" โœ… Rainfall sufficient
Sep 4.3" 7.7" 0" โœ… Rainfall sufficient
Oct 4.3" 4.4" 0" โœ… Rainfall sufficient
Nov 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Dec โ€” 3.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Upton County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Thai 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" โ€” every day above 50ยฐF 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.

Thai Basil needs ~1,375 GDD — county provides 5,214 GDD Excellent fit

Thai Basil Planting Timeline โ€” Upton County, TX

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors January 30 Jan 30 โ€“ Feb 13
Transplant Outdoors April 3 Apr 3 โ€“ Apr 17
Direct Sow March 27 Mar 27 โ€“ Apr 17
Harvest May 29 May 29 โ€“ Jul 31

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

50โ€“75 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

237 days in Upton County

Growing Tips for Thai Basil in Upton County

Direct sow Thai Basil outdoors after March 20 in Upton County when soil has warmed and frost danger has passed.

Sandy soil in Upton County dries quickly โ€” mulch Thai Basil with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 96ยฐF in Upton County, provide afternoon shade for Thai Basil and water deeply in the morning.

General growing tips

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

  • Rue
  • Sage

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Thai Basil in Upton County, TX?

Upton County is in Zone 7b with an average last frost of March 20. Plan your Thai Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Upton County, TX?

Upton County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 20 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Upton County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Upton County, TX. Local conditions may vary. Last updated: April 2026.