When to Plant Lavender in Waukesha County, WI
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.
Waukesha County, Wisconsin is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 12, giving you a growing season of approximately 168 days.
At an elevation of 1,352 feet, Waukesha County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Lavender to ensure they mature before fall.
Waukesha County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.3
Drainage
Well Drained
Plant Planting Risk Windows
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
Lavender Planting Timeline — Waukesha County, WI
Lavender Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 4 | May 4 – May 18 |
| Harvest | August 3 | Aug 3 – Oct 19 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
90–200 days
Soil pH
6.5 – 8
USDA Zone
Zone 5a
Growing Season
168 days
Growing Tips for Waukesha 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
Lavender in Other Locations
Frequently Asked Questions
When should I plant Lavender in Waukesha County, WI?
Waukesha County is in Zone 5a with an average last frost of April 27. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.
What planting zone is Waukesha County, WI?
Waukesha County, Wisconsin is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 12.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Waukesha County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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