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When to Plant Lavender in King 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.

King County, Texas is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.

At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99ยฐF, so Lavender may need afternoon shade and extra watering during peak heat. 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.

King County, TX (Zone 7b) Long season
221 days
Last Spring Frost March 31
221 growing days
First Fall Frost November 7

King County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Mar 30 🍅 Harvest: Jun 29 – Nov 9
Recommended (50%) ✗ May not fit
Transplant: Apr 7 🍅 Harvest: Jul 7 – Nov 17
Safe Start (90%) ✗ May not fit
Transplant: Apr 22 🍅 Harvest: Jul 22 – Dec 2

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.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/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

Lavender needs ~3,516 GDD — county provides 5,359 GDD Excellent fit

Lavender Planting Timeline โ€” King County, TX

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors April 7 Apr 7 โ€“ Apr 21
Harvest July 7 Jul 7 โ€“ Nov 17

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

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

90โ€“200 days

Soil pH

6.5 โ€“ 8

USDA Zone

Zone 7b

Growing Season

221 days

Growing Tips for King County

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Lavender in King County, TX?

King County is in Zone 7b with an average last frost of March 31. Plan your Lavender planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is King County, TX?

King County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 7.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help King County gardeners in Zone 7b 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 King County, TX. Local conditions may vary. Last updated: April 2026.