When to Plant Thai Basil in Polk County, TN
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.
Polk County, Tennessee is in USDA Zone 7a. The average last spring frost is April 19 and the first fall frost is October 19, giving you a growing season of approximately 183 days.
At an elevation of 1,255 feet, Polk County receives approximately 43.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Thai Basil during the growing season.
Polk County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.5
Drainage
Well Drained
Plant Planting Risk Windows
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Thai Basil Planting Timeline — Polk County, TN
Thai Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 1 | Mar 1 – Mar 15 |
| Transplant Outdoors | May 3 | May 3 – May 17 |
| Direct Sow | April 26 | Apr 26 – May 17 |
| Harvest | June 28 | Jun 28 – Aug 30 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| 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
6 – 7
USDA Zone
Zone 7a
Growing Season
183 days
Growing Tips for Polk 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
Level Up Your Garden
Thai Basil in Other Locations
Frequently Asked Questions
When should I plant Thai Basil in Polk County, TN?
Polk County is in Zone 7a with an average last frost of April 19. Plan your Thai Basil planting based on this frost date — see the calendar above for exact timing.
What planting zone is Polk County, TN?
Polk County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 19 and first fall frost is October 19.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Polk County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.