Frost dates in Denver, CO

The average last spring frost in Denver is around May 3 and the first fall frost is around October 9. That gives Denver an average growing season of about 159 days.

Last spring frost

Early (10% chance after)April 18
Average (50%)May 3
Late (90%)May 19

First fall frost

Early (10%)September 20
Average (50%)October 9
Late (90% chance before)October 22

See the Denver planting calendar →