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When to Plant Lavender in Cass 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.

Cass County, Texas is in USDA Zone 8a. The average last spring frost is March 14 and the first fall frost is November 16, giving you a growing season of approximately 247 days.

At an elevation of 392 feet, Cass County receives approximately 71.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94ยฐF, providing good warmth for Lavender during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Lavender will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lavender root diseases.

Cass County, TX (Zone 8a) Long season
247 days
Last Spring Frost March 14
247 growing days
First Fall Frost November 16

Cass County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.6-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Mar 13 🍅 Harvest: Jun 12 – Nov 13
Recommended (50%) ✗ May not fit
Transplant: Mar 21 🍅 Harvest: Jun 20 – Nov 21
Safe Start (90%) ✗ May not fit
Transplant: Apr 12 🍅 Harvest: Jul 12 – Dec 13

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 Cass County

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

Soil pH

Your soil pH (5.6โ€“6.7) is more acidic than Lavender prefers (6.5โ€“8.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Cass County warms quickly in spring but drains fast. Lavender will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Lavender.

Organic Matter

Organic matter is low (1.9%). Add 2-3 inches of compost before planting 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
1.2″/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€” 2" 0" โ„๏ธ Dormant
Feb โ€” 2.5" 0" โ„๏ธ Dormant
Mar 1.3" 4.3" 0" โœ… Rainfall sufficient
Apr 1.3" 6.6" 0" โœ… Rainfall sufficient
May 1.3" 11.3" 0" โœ… Rainfall sufficient
Jun 1.3" 12.4" 0" โœ… Rainfall sufficient
Jul 1.3" 8.9" 0" โœ… Rainfall sufficient
Aug 1.3" 8.7" 0" โœ… Rainfall sufficient
Sep 1.3" 6.7" 0" โœ… Rainfall sufficient
Oct 1.3" 4.3" 0" โœ… Rainfall sufficient
Nov 1.3" 2.4" 0" โœ… Rainfall sufficient
Dec โ€” 1.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Cass 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 ~2,972 GDD — county provides 5,063 GDD Excellent fit

Lavender Planting Timeline โ€” Cass County, TX

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors March 21 Mar 21 โ€“ Apr 4
Harvest June 20 Jun 20 โ€“ Nov 21

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: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

247 days in Cass County

Growing Tips for Lavender in Cass County

Direct sow Lavender outdoors after March 14 in Cass County when soil has warmed and frost danger has passed.

Sandy soil in Cass County dries quickly โ€” mulch Lavender with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With 72" of annual rainfall in Cass 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 Cass County, TX?

Cass County is in Zone 8a with an average last frost of March 14. Plan your Lavender planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cass County, TX?

Cass County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 14 and first fall frost is November 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cass County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.

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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 Cass County, TX. Local conditions may vary. Last updated: April 2026.