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When to Plant Lavender in Dallas County, TX

Dallas County, Texas Zone 8b May

This month in Dallas County, Texas

May is a pivotal month for Dallas County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost March 8
Avg. first frost November 20
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
A few tasks this May that'll pay off in June
  • First harvests: lavender

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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.

Dallas County, Texas is in USDA Zone 8b. The average last spring frost is March 8 and the first fall frost is November 20, giving you a growing season of approximately 257 days.

At an elevation of 67 feet, Dallas County receives approximately 65.7 inches of rainfall annually with predominantly clay soil. Summer highs average 97°F, so Lavender may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Lavender, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lavender root diseases.

Dallas County, TX (Zone 8b) Long season
257 days
Last Spring Frost March 8
257 growing days
First Fall Frost November 20
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Dallas County Soil Profile

Soil Type

Clay

Soil pH

6.7-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (2 days to spare)
Transplant: Mar 8 🍅 Harvest: Jun 7 – Nov 8
Recommended (50%) ✓ Fits season (5 days to spare)
Transplant: Mar 15 🍅 Harvest: Jun 14 – Nov 15
Safe Start (90%) ✗ May not fit
Transplant: Apr 16 🍅 Harvest: Jul 16 – Dec 17

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 Dallas County

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

Soil pH

Your soil pH (6.7–8.4) overlaps with Lavender's range (6.5–8.0), though not a perfect match.

Soil Texture

Heavy clay soil (48% clay) in Dallas County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (2.6%). 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
1.1″/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 1.5" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 1.3" 4.4" 0" ✅ Rainfall sufficient
Apr 1.3" 7.1" 0" ✅ Rainfall sufficient
May 1.3" 9.2" 0" ✅ Rainfall sufficient
Jun 1.3" 10.4" 0" ✅ Rainfall sufficient
Jul 1.3" 7.4" 0" ✅ Rainfall sufficient
Aug 1.3" 8.3" 0" ✅ Rainfall sufficient
Sep 1.3" 6" 0" ✅ Rainfall sufficient
Oct 1.3" 4.6" 0" ✅ Rainfall sufficient
Nov 1.3" 2.4" 0" ✅ Rainfall sufficient
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Dallas County). Supplement amounts are based on average rainfall — 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" — 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.

Lavender needs ~3,299 GDD — county provides 5,846 GDD Excellent fit

Lavender Planting Timeline — Dallas County, TX

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors March 15 Mar 15 – Mar 29
Harvest June 14 Jun 14 – Nov 15

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

Month-by-Month Timeline

MonthActivities
January
February
March Transplant Outdoors
April
May
June Harvest
July Harvest
August Harvest
September Harvest
October Harvest
November Harvest
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

90–200 days

🧪 Soil pH

Needs 6.5–8 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

257 days in Dallas County

Growing Tips for Lavender in Dallas County

Direct sow Lavender outdoors after March 08 in Dallas County when soil has warmed and frost danger has passed.

With Dallas County's clay soil (48% clay), work in 3-4 inches of compost before planting Lavender. Avoid tilling when soil is wet to prevent compaction.

With summer highs reaching 97°F in Dallas County, provide afternoon shade for Lavender and water deeply in the morning.

With 66" of annual rainfall in Dallas County, ensure good drainage for Lavender — 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 Dallas County, TX?

Dallas County is in Zone 8b with an average last frost of March 8. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dallas County, TX?

Dallas County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 8 and first fall frost is November 20.

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Your Dallas County Garden Planner — Free

A 24-page printable planner built for Dallas County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Dallas County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.