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When to Plant Lavender in Hamilton County, TN

Lavender is a fragrant perennial herb with silvery foliage and purple flower spikes. It is prized for its essential oils, culinary uses, and ornamental beauty.

Hamilton County, Tennessee is in USDA Zone 7a. The average last spring frost is March 28 and the first fall frost is November 1, giving you a growing season of approximately 218 days.

At an elevation of 3,918 feet, Hamilton County receives approximately 51.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93ยฐF, providing good warmth for Lavender during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lavender root diseases.

Hamilton County, TN (Zone 7a) Long season
218 days
Last Spring Frost March 28
218 growing days
First Fall Frost November 1

Hamilton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Mar 28 🍅 Harvest: Jun 27 – Nov 7
Recommended (50%) ✗ May not fit
Transplant: Apr 4 🍅 Harvest: Jul 4 – Nov 14
Safe Start (90%) ✗ May not fit
Transplant: Apr 24 🍅 Harvest: Jul 24 – Dec 4

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 Hamilton County

How your county's soil matches Lavender's growing requirements.

Soil pH

Your soil pH (5.6โ€“6.9) is more acidic than Lavender prefers (6.5โ€“8.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Hamilton County is excellent for Lavender โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.9%). Annual compost additions will help Lavender.

How to Plant Lavender

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Plant Water Budget

Plant needs
0.3″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Lavender

Lavender needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.

Month Lavender Needs Rainfall You Supplement Action
Jan โ€” 4.3" 0" โ„๏ธ Dormant
Feb โ€” 4.5" 0" โ„๏ธ Dormant
Mar 1.3" 4.8" 0" โœ… Rainfall sufficient
Apr 1.3" 4" 0" โœ… Rainfall sufficient
May 1.3" 4.3" 0" โœ… Rainfall sufficient
Jun 1.3" 4.6" 0" โœ… Rainfall sufficient
Jul 1.3" 5.4" 0" โœ… Rainfall sufficient
Aug 1.3" 5.2" 0" โœ… Rainfall sufficient
Sep 1.3" 3.8" 0" โœ… Rainfall sufficient
Oct 1.3" 2.7" 0" โœ… Rainfall sufficient
Nov 1.3" 4.2" 0" โœ… Rainfall sufficient
Dec โ€” 3.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Hamilton County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Lavender 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" โ€” every day above 50ยฐF 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.

Lavender needs ~2,864 GDD — county provides 4,305 GDD Excellent fit

Lavender Planting Timeline โ€” Hamilton County, TN

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors April 4 Apr 4 โ€“ Apr 18
Harvest July 4 Jul 4 โ€“ Nov 14

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May โ€”
June โ€”
July Harvest
August Harvest
September Harvest
October Harvest
November Harvest
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.3"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“200 days

๐Ÿงช Soil pH

Needs 6.5โ€“8 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

218 days in Hamilton County

Growing Tips for Lavender in Hamilton County

Direct sow Lavender outdoors after March 28 in Hamilton County when soil has warmed and frost danger has passed.

General growing tips

Plant in well-drained, sandy soil. Avoid heavy mulching around the crown. Prune after flowering but do not cut into old wood. Lavender resents wet winter conditions.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lavender in Hamilton County, TN?

Hamilton County is in Zone 7a with an average last frost of March 28. Plan your Lavender planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hamilton County, TN?

Hamilton County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is March 28 and first fall frost is November 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Hamilton County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Hamilton County, TN. Local conditions may vary. Last updated: April 2026.