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When to Plant Thai Basil in Pulaski County, IL

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.

Pulaski County, Illinois is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 22, giving you a growing season of approximately 196 days.

At an elevation of 1,244 feet, Pulaski County receives approximately 30.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Thai Basil during the growing season.

Pulaski County, IL (Zone 6b) Moderate season
196 days
Last Spring Frost April 9
196 growing days
First Fall Frost October 22

Pulaski County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (64 days to spare)
Start indoors: Feb 13 Transplant: Apr 17 🍅 Harvest: Jun 12 – Aug 14
Recommended (50%) ✓ Fits season (63 days to spare)
Start indoors: Feb 19 Transplant: Apr 23 🍅 Harvest: Jun 18 – Aug 20
Safe Start (90%) ✓ Fits season (62 days to spare)
Start indoors: Mar 3 Transplant: May 5 🍅 Harvest: Jun 30 – Sep 1

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 707 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Thai Basil needs ~859 GDD — county provides 2,695 GDD Excellent fit

Thai Basil Planting Timeline โ€” Pulaski County, IL

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors February 19 Feb 19 โ€“ Mar 5
Transplant Outdoors April 23 Apr 23 โ€“ May 7
Direct Sow April 16 Apr 16 โ€“ May 7
Harvest June 18 Jun 18 โ€“ Aug 20

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

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“75 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

196 days

Growing Tips for Pulaski 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

Level Up Your Garden

Frequently Asked Questions

When should I plant Thai Basil in Pulaski County, IL?

Pulaski County is in Zone 6b with an average last frost of April 9. Plan your Thai Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pulaski County, IL?

Pulaski County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

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