Perennial Flower

When to Plant Lavender in Colorado

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

The Short Answer

In Colorado, plant lavender based on your regional frost dates. Front Range (Denver) has a last frost around May 1 - May 15, while Mountain Regions sees frost end around Jun 1 - Jun 20. High altitude means intense sun but cool nights. Low humidity. Hail risk in late spring. Short but intense growing...

Colorado Frost Dates

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

Region Zones Last Frost (Spring) First Frost (Fall)
Front Range (Denver) 5a, 5b, 6a May 1 - May 15 Sep 25 - Oct 10
Western Slope 4b, 5a, 5b, 6a May 10 - Jun 1 Sep 15 - Oct 5
Mountain Regions 3a, 3b, 4a, 4b Jun 1 - Jun 20 Aug 25 - Sep 15

Lavender Planting Schedule for Colorado

Front Range (Denver) (Zones 5a, 5b, 6a)

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

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

Western Slope (Zones 4b, 5a, 5b, 6a)

Average last frost: May 10 - Jun 1 · Average first frost: Sep 15 - Oct 5

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

Mountain Regions (Zones 3a, 3b, 4a, 4b)

Average last frost: Jun 1 - Jun 20 · Average first frost: Aug 25 - Sep 15

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

Growing Lavender in Colorado

Lavender in Colorado'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 Colorado

Alkaline clay soils common along Front Range. Rocky, thin soils in mountains. Amend heavily with compost and sulfur to lower pH.

Colorado Climate & Growing Season

High altitude means intense sun but cool nights. Low humidity. Hail risk in late spring. Short but intense growing season at elevation.

Growing season length varies across Colorado: Front Range (Denver) (5a, 5b, 6a) has a last frost around May 1 - May 15, while Mountain Regions (3a, 3b, 4a, 4b) sees frost end around Jun 1 - Jun 20. 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 Colorado, but your exact planting dates depend on which region you're in. Front Range (Denver) gardeners should plan around a May 1 - May 15 last frost, while those in Mountain Regions can typically plant later. 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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