Perennial Flower

When to Plant Lavender in Iowa

Fragrant, drought-tolerant, and beloved by pollinators. Once established, lavender rewards you for years.

The Short Answer

In Iowa, plant lavender based on your regional frost dates. Northern Iowa has a last frost around May 5 - May 20, while Southern Iowa sees frost end around Apr 20 - May 5. Continental climate. Cold winters, warm humid summers. Good growing season with adequate rainfall.

Iowa Frost Dates

Your planting dates depend on which part of Iowa you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Northern Iowa 4b, 5a May 5 - May 20 Sep 20 - Oct 5
Central Iowa 5a, 5b Apr 25 - May 10 Oct 1 - Oct 15
Southern Iowa 5b Apr 20 - May 5 Oct 5 - Oct 20

Lavender Planting Schedule for Iowa

Northern Iowa (Zones 4b, 5a)

Average last frost: May 5 - May 20 · Average first frost: Sep 20 - Oct 5

Start Seeds Indoors
10 wks before frost
Transplant Outside
2 wks after frost

Central Iowa (Zones 5a, 5b)

Average last frost: Apr 25 - May 10 · Average first frost: Oct 1 - Oct 15

Start Seeds Indoors
10 wks before frost
Transplant Outside
2 wks after frost

Southern Iowa (Zones 5b)

Average last frost: Apr 20 - May 5 · Average first frost: Oct 5 - Oct 20

Start Seeds Indoors
10 wks before frost
Transplant Outside
2 wks after frost

Growing Lavender in Iowa

Lavender in Iowa's Climate

Lavender is challenging in cold climates — wet clay soil and cold winters are its enemies. English lavender (Hidcote, Munstead) is hardiest to zone 5. The key is drainage — raised beds with gravel and sand amendment are mandatory. Sandy soils of western Michigan and similar areas have a natural advantage. Mulch with pea gravel, not organic mulch, to prevent crown rot.

Soil Considerations for Iowa

Outstanding black prairie soils. Some of the richest agricultural land in the world. Minimal amendment needed.

Iowa Climate & Growing Season

Continental climate. Cold winters, warm humid summers. Good growing season with adequate rainfall.

Growing season length varies across Iowa: Northern Iowa (4b, 5a) has a last frost around May 5 - May 20, while Southern Iowa (5b) sees frost end around Apr 20 - May 5. This difference matters for lavender — adjust your planting dates to match your specific region.

Growing Tips

Needs excellent drainage — clay soil is lavender's enemy. Don't prune into old wood. English varieties (Lavandula angustifolia) are hardiest.

Companion Planting

Plant lavender alongside these companions for better growth:

Roses Thyme Sage

The Bottom Line

Lavender can be grown successfully across Iowa, but your exact planting dates depend on which region you're in. Northern Iowa gardeners should plan around a May 5 - May 20 last frost, while those in Southern Iowa can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

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