When to Plant Thai Basil in Henry 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.
Henry County, Tennessee is in USDA Zone 7a. The average last spring frost is April 6 and the first fall frost is October 28, giving you a growing season of approximately 205 days.
At an elevation of 1,382 feet, Henry County receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Thai Basil during the growing season.
Henry County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-7.1
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.
Soil Compatibility in Henry County
How your county's soil matches Thai Basil's growing requirements.
Soil pH
Your soil pH (5.8–7.1) overlaps with Thai Basil's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Henry County is excellent for Thai Basil — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Thai Basil.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Thai Basil.
How to Plant Thai Basil
Succession Planting Thai Basil
Sow every 5.7 weeks. Last sowing by Aug 14 to harvest before frost.
Plant Water Budget
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 | — | 3.9" | 0" | ❄️ Dormant |
| Feb | — | 3.7" | 0" | ❄️ Dormant |
| Mar | — | 3.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| May | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Jun | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Jul | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Aug | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Sep | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Oct | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Nov | — | 3.5" | 0" | ❄️ Dormant |
| Dec | — | 3.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Henry County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Thai Basil Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Thai Basil Planting Timeline — Henry County, TN
Thai Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 16 | Feb 16 – Mar 2 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | June 15 | Jun 15 – Aug 17 |
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
1"/week · Natural rainfall sufficient
📅 Days to Maturity
50–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
205 days in Henry County
Growing Tips for Thai Basil in Henry County
Direct sow Thai Basil outdoors after April 06 in Henry County when soil has warmed and frost danger has passed.
General growing tips
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 Henry County, TN?
Henry County is in Zone 7a with an average last frost of April 6. Plan your Thai Basil planting based on this frost date — see the calendar above for exact timing.
What planting zone is Henry County, TN?
Henry County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 6 and first fall frost is October 28.
Plan Your Garden with Confidence
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