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When to plant Thai Basil in Edgar County, IL

Edgar County's climate puts the Thai Basil spring window between April 25 and May 16. time plantings around the expected last-frost window for best survival.

When to Plant Thai Basil in Edgar 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.

Edgar County, Illinois is in USDA Zone 6a. The average last spring frost is April 18 and the first fall frost is October 17, giving you a growing season of approximately 182 days.

At an elevation of 1,272 feet, Edgar County receives approximately 41.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Thai Basil to ensure they mature before fall.

Edgar County, IL (Zone 6a) Moderate season
182 days
Last Spring Frost April 18
182 growing days
First Fall Frost October 17

Edgar County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

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 1.6" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.3" 3.8" 0.5" 💧 Light watering
May 4.3" 4.8" 0" ✅ Rainfall sufficient
Jun 4.3" 5.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4.9" 0" ✅ Rainfall sufficient
Aug 4.3" 3.8" 0.5" 💧 Light watering
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 3.3" 1" 💧 Light watering
Nov 2.9" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Edgar County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Thai Basil Planting Timeline — Edgar County, IL

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 – Mar 14
Transplant Outdoors May 2 May 2 – May 16
Direct Sow April 25 Apr 25 – May 16
Harvest June 27 Jun 27 – Aug 29

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Direct Sow
May Transplant Outdoors Direct Sow
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 6a

📆 Growing Season

182 days in Edgar County

Growing Tips for Edgar 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 Edgar County, IL?

Edgar County is in Zone 6a with an average last frost of April 18. Plan your Thai Basil planting based on this frost date — see the calendar above for exact timing.

What planting zone is Edgar County, IL?

Edgar County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 18 and first fall frost is October 17.

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

In Edgar County, IL, plant Thai Basil after the last frost (around April 18) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Edgar County, IL for Thai Basil?

Edgar County sits in USDA Zone 6a. Thai Basil grows reliably in zones 4a through 11b, so it's a good fit here.

Can Thai Basil grow in Edgar County's climate?

Yes — Thai Basil grows well in Edgar County's temperate climate. Edgar County averages a 182-day frost-free season, with last frost around April 18 and first frost around October 17.

🌱

Your Edgar County Garden Planner — Free

A 22-page printable planner built for Edgar County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Edgar County, IL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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