When to plant Thai Basil in Alexander County, IL
Aim to plant Thai Basil in Alexander County on or after April 17; the window stays open through May 8. Alexander County's 194-day frost-free season gives you enough for a full main crop and a short fall succession.
When to Plant Thai Basil in Alexander 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.
Alexander County, Illinois is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 21, giving you a growing season of approximately 194 days.
At an elevation of 1,260 feet, Alexander County receives approximately 38.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Thai Basil during the growing season.
Alexander County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Thai Basil Planting Timeline — Alexander County, IL
Thai Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | June 19 | Jun 19 – Aug 21 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors 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 7a
📆 Growing Season
194 days in Alexander County
Growing Tips for Alexander 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
Check more plant combinations with our Companion Planting Checker →
Thai Basil in Other Locations
Frequently Asked Questions
When should I plant Thai Basil in Alexander County, IL?
Alexander County is in Zone 7a with an average last frost of April 10. Plan your Thai Basil planting based on this frost date — see the calendar above for exact timing.
What planting zone is Alexander County, IL?
Alexander County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 21.
When should I plant Thai Basil in Alexander County, IL?
In Alexander County, IL, plant Thai Basil after the last frost (around April 10) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Alexander County, IL for Thai Basil?
Alexander County sits in USDA Zone 7a. Thai Basil grows reliably in zones 4a through 11b, so it's a good fit here.
Can Thai Basil grow in Alexander County's climate?
Yes — Thai Basil grows well in Alexander County's temperate climate. Alexander County averages a 194-day frost-free season, with last frost around April 10 and first frost around October 21.
Your Alexander County Garden Planner — Free
A 22-page printable planner built for Alexander County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.