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When to Plant Lavender in Alexander County, IL

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.

Alexander County, Illinois is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 21, giving you a growing season of approximately 194 days.

At an elevation of 1,260 feet, Alexander County receives approximately 38.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Lavender during the growing season.

Alexander County, IL (Zone 7a) Moderate season
194 days
Last Spring Frost April 10
194 growing days
First Fall Frost October 21

Alexander County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 12 🍅 Harvest: Jul 12 – Nov 22
Recommended (50%) ✗ May not fit
Transplant: Apr 17 🍅 Harvest: Jul 17 – Nov 27
Safe Start (90%) ✗ May not fit
Transplant: May 1 🍅 Harvest: Jul 31 – Dec 11

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
0.8″/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 ~2,320 GDD — county provides 3,104 GDD Excellent fit

Lavender Planting Timeline โ€” Alexander County, IL

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors April 17 Apr 17 โ€“ May 1
Harvest July 17 Jul 17 โ€“ Nov 27

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 Transplant Outdoors
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 7a

Growing Season

194 days

Growing Tips for Alexander 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 Alexander County, IL?

Alexander County is in Zone 7a with an average last frost of April 10. Plan your Lavender planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Alexander County, IL?

Alexander County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 21.

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Plan Your Garden with Confidence

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