Frost dates · 22 cities · zones 5b–7a
Colorado frost dates, city by city
Median last spring frost across 22 Colorado cities runs from April 26 in Pueblo to May 9 in Parker.
| City | Zone | Last frost median | First frost median | Season | Jan → Dec |
|---|---|---|---|---|---|
| Denver | 6a | May 4 | Oct 8 | 156 d | |
| Colorado Springs | 6a | May 3 | Oct 8 | 158 d | |
| Aurora | 6a | May 5 | Oct 9 | 156 d | |
| Fort Collins | 5b | May 3 | Oct 6 | 154 d | |
| Lakewood | 6a | May 3 | Oct 7 | 155 d | |
| Thornton | 6a | May 2 | Oct 11 | 160 d | |
| Arvada | 6a | May 5 | Oct 5 | 151 d | |
| Westminster | 6a | May 2 | Oct 11 | 160 d | |
| Greeley | 5b | May 2 | Oct 8 | 159 d | |
| Pueblo | 6a | Apr 26 | Oct 13 | 166 d | |
| Centennial | 6a | May 5 | Oct 8 | 154 d | |
| Boulder | 6a | May 6 | Oct 5 | 151 d | |
| Longmont | 5b | May 7 | Oct 5 | 151 d | |
| Castle Rock | 5b | May 9 | Oct 2 | 143 d | |
| Loveland | 5b | May 3 | Oct 6 | 154 d | |
| Broomfield | 6a | May 2 | Oct 11 | 160 d | |
| Grand Junction | 7a | Apr 28 | Oct 16 | 171 d | |
| Commerce City | 6a | May 3 | Oct 7 | 155 d | |
| Parker | 5b | May 9 | Oct 3 | 145 d | |
| Littleton | 6a | May 2 | Oct 11 | 160 d | |
| Brighton | 5b | May 3 | Oct 7 | 155 d | |
| Windsor | 5b | May 3 | Oct 6 | 154 d |
Medians from NOAA NCEI 1991–2020 U.S. Climate Normals at each city's nearest qualifying station; zones from the 2023 USDA Plant Hardiness Zone Map. Open a city for the 1-in-10-year dates, the station, and a planting calendar for every sauce crop.
All states →Build a plan from your ZIP →Earliest: Pueblo (Apr 26) · Latest: Parker (May 9)