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When to Plant Thai Basil in Blair County, PA

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.

Blair County, Pennsylvania is in USDA Zone 6a. The average last spring frost is April 25 and the first fall frost is October 19, giving you a growing season of approximately 177 days.

At an elevation of 41 feet, Blair County receives approximately 43.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90ยฐF, providing good warmth for Thai Basil during the growing season.

Blair County, PA (Zone 6a) Moderate season
177 days
Last Spring Frost April 25
177 growing days
First Fall Frost October 19

Blair County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.8

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 โ€” 3.6" 0" โ„๏ธ Dormant
Feb โ€” 2.7" 0" โ„๏ธ Dormant
Mar โ€” 3.8" 0" โ„๏ธ Dormant
Apr 4.3" 4" 0.3" ๐Ÿ’ง Light watering
May 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jun 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jul 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Aug 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Sep 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Oct 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Nov โ€” 3.1" 0" โ„๏ธ Dormant
Dec โ€” 3.6" 0" โ„๏ธ Dormant

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

Thai Basil Planting Timeline โ€” Blair County, PA

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors March 7 Mar 7 โ€“ Mar 21
Transplant Outdoors May 9 May 9 โ€“ May 23
Direct Sow May 2 May 2 โ€“ May 23
Harvest July 4 Jul 4 โ€“ Sep 5

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

50โ€“75 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

177 days in Blair County

Growing Tips for Blair 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

  • Rue
  • Sage

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Thai Basil in Blair County, PA?

Blair County is in Zone 6a with an average last frost of April 25. Plan your Thai Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Blair County, PA?

Blair County, Pennsylvania is in USDA Hardiness Zone 6a. The average last spring frost is April 25 and first fall frost is October 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Blair County gardeners in Zone 6a 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 Blair County, PA. Local conditions may vary. Last updated: April 2026.