Herb

When to Plant Cilantro in Colorado

You either love it or your genetics say no. For the cilantro lovers, it's an essential herb that bolts fast in heat.

The Short Answer

Cilantro are planted in fall in Colorado, 6 weeks before your first frost date. That means planting around Sep 25 - Oct 10 in Front Range (Denver).

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

Cilantro 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

Direct Sow
2 wks before frost
Fall Planting
6 wks before first frost

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

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

Direct Sow
2 wks before frost
Fall Planting
6 wks before first frost

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

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

Direct Sow
2 wks before frost
Fall Planting
6 wks before first frost

Growing Cilantro in Colorado

Cilantro in Colorado's Climate

Your cool climate extends the cilantro season significantly. Direct sow from mid-April — the herb may produce for 6-8 weeks before bolting versus 3-4 weeks in warm zones. Northern Michigan and Minnesota's moderate summer temperatures are genuine cilantro advantages. Fall cilantro from an August sowing is highly productive.

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 cilantro — adjust your planting dates to match your specific region.

Growing Tips

Bolts quickly in heat — succession plant every 3 weeks and grow in partial shade during summer. Let some bolt for coriander seeds.

Companion Planting

Plant cilantro alongside these companions for better growth:

Beans Peas Tomatoes

Keep cilantro away from:

Fennel

The Bottom Line

Cilantro 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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