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When to Plant Thai Basil in Randall 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.

Randall County, Texas is in USDA Zone 7a. The average last spring frost is April 15 and the first fall frost is October 24, giving you a growing season of approximately 192 days.

At an elevation of 1,230 feet, Randall County receives approximately 57.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95ยฐF, 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.

Randall County, TX (Zone 7a) Moderate season
192 days
Last Spring Frost April 15
192 growing days
First Fall Frost October 24

Randall County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.7-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (55 days to spare)
Start indoors: Feb 23 Transplant: Apr 27 🍅 Harvest: Jun 22 – Aug 24
Recommended (50%) ✓ Fits season (59 days to spare)
Start indoors: Feb 25 Transplant: Apr 29 🍅 Harvest: Jun 24 – Aug 26
Safe Start (90%) ✓ Fits season (57 days to spare)
Start indoors: Mar 12 Transplant: May 14 🍅 Harvest: Jul 9 – Sep 10

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 Randall County

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

Soil pH

Your soil pH (7.7โ€“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 Randall County warms quickly in spring but drains fast. Thai Basil will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Thai Basil.

Organic Matter

Organic matter is low (1.1%). 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

4
successive plantings in your 192-day season

Sow every 5.7 weeks. Last sowing by Aug 10 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.3″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 100 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€” 4.3" 0" โ„๏ธ Dormant
Feb โ€” 3.3" 0" โ„๏ธ Dormant
Mar โ€” 3.2" 0" โ„๏ธ Dormant
Apr 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
May 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Jun 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Jul 4.3" 8.9" 0" โœ… Rainfall sufficient
Aug 4.3" 11.2" 0" โœ… Rainfall sufficient
Sep 4.3" 7.7" 0" โœ… Rainfall sufficient
Oct 4.3" 5.6" 0" โœ… Rainfall sufficient
Nov โ€” 3.3" 0" โ„๏ธ Dormant
Dec โ€” 4.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Randall 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 ~1,328 GDD — county provides 4,080 GDD Excellent fit

Thai Basil Planting Timeline โ€” Randall County, TX

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 โ€“ Mar 11
Transplant Outdoors April 29 Apr 29 โ€“ May 13
Direct Sow April 22 Apr 22 โ€“ May 13
Harvest June 24 Jun 24 โ€“ Aug 26

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Harvest
August Harvest
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 7a

๐Ÿ“† Growing Season

192 days in Randall County

Growing Tips for Thai Basil in Randall County

Direct sow Thai Basil outdoors after April 15 in Randall County when soil has warmed and frost danger has passed.

Sandy soil in Randall 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.

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 Randall County, TX?

Randall County is in Zone 7a with an average last frost of April 15. Plan your Thai Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Randall County, TX?

Randall County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 15 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Randall County gardeners in Zone 7a 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 Randall County, TX. Local conditions may vary. Last updated: April 2026.