Blog

When to Plant Lavender in Callahan County, TX

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.

Callahan County, Texas is in USDA Zone 7b. The average last spring frost is March 21 and the first fall frost is November 16, giving you a growing season of approximately 240 days.

At an elevation of 4,241 feet, Callahan County receives approximately 59.1 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Lavender during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lavender root diseases.

Callahan County, TX (Zone 7b) Long season
240 days
Last Spring Frost March 21
240 growing days
First Fall Frost November 16

Callahan County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (13 days to spare)
Transplant: Mar 17 🍅 Harvest: Jun 16 – Oct 27
Recommended (50%) ✓ Fits season (9 days to spare)
Transplant: Mar 28 🍅 Harvest: Jun 27 – Nov 7
Safe Start (90%) ✓ Fits season (4 days to spare)
Transplant: Apr 19 🍅 Harvest: Jul 19 – Nov 29

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 Callahan County

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

Soil pH

Your soil pH (6.8โ€“7.4) is within Lavender's preferred range (6.5โ€“8.0).

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). 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
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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€” 1.7" 0" โ„๏ธ Dormant
Feb โ€” 1.9" 0" โ„๏ธ Dormant
Mar 1.3" 3.3" 0" โœ… Rainfall sufficient
Apr 1.3" 5.9" 0" โœ… Rainfall sufficient
May 1.3" 7.8" 0" โœ… Rainfall sufficient
Jun 1.3" 11" 0" โœ… Rainfall sufficient
Jul 1.3" 8.5" 0" โœ… Rainfall sufficient
Aug 1.3" 6.1" 0" โœ… Rainfall sufficient
Sep 1.3" 5.7" 0" โœ… Rainfall sufficient
Oct 1.3" 3.8" 0" โœ… Rainfall sufficient
Nov 1.3" 1.8" 0" โœ… Rainfall sufficient
Dec โ€” 1.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Callahan 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 ~2,646 GDD — county provides 4,380 GDD Excellent fit

Lavender Planting Timeline โ€” Callahan County, TX

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors March 28 Mar 28 โ€“ Apr 11
Harvest June 27 Jun 27 โ€“ Nov 7

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Transplant Outdoors
April Transplant Outdoors
May โ€”
June Harvest
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: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

240 days in Callahan County

Growing Tips for Lavender in Callahan County

Direct sow Lavender outdoors after March 21 in Callahan County when soil has warmed and frost danger has passed.

With 59" of annual rainfall in Callahan County, ensure good drainage for Lavender โ€” excess moisture can promote root rot and fungal diseases.

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 Callahan County, TX?

Callahan County is in Zone 7b with an average last frost of March 21. Plan your Lavender planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Callahan County, TX?

Callahan County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 21 and first fall frost is November 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Callahan County gardeners in Zone 7b 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.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Callahan County, TX. Local conditions may vary. Last updated: April 2026.