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Frost dates for Denver, Colorado

In a typical year, Denver’s last spring frost lands around Apr 30 and the first fall frost around Oct 12, a growing season of about 165 days. These are odds drawn from 30-year NOAA climate normals, not a promise. USDA zone 6a.

Right now the typical frost season has arrived; planting waits for spring.

Last spring frost and first fall frost odds for Denver, Colorado
OddsLast spring frostFirst fall frost
10 percentApr 15Sep 28
50 percentApr 30Oct 12
90 percentMay 13Oct 26

A 10 percent year is an early year, a 90 percent year a late one. Frost-sensitive planting usually waits for the 90 percent side of the last-frost band.

Soil in Denver is typically around 51°F at 4 inches this time of year, estimated from the last two weeks of normal air temperatures.

See what is plantable in your ZIP with the what-to-plant lookup.

Common questions

When is the last frost in Denver, Colorado?

Denver’s last spring frost falls around April 30 in a typical year. One year in ten it is done by April 15, and one year in ten frost holds on until May 13. Frost-sensitive planting usually waits for the late side of that band.

When is the first fall frost in Denver?

The first fall frost arrives around October 12 in a typical year, as early as September 28 in an early year and as late as October 26 in a late one.

How long is the growing season in Denver?

About 165 days, counted between the typical last spring frost and the typical first fall frost.

What USDA zone is Denver in?

Denver is in USDA hardiness zone 6a under the 2023 USDA Plant Hardiness Zone Map.

Dates come from 30-year NOAA climate normals for the nearest reporting station. They describe odds, not a forecast.

Nearby cities

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