Colorado frost dates: C
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Cahone | May 11 | Oct 12 | 154 d | 6b |
| Calhan | May 6 | Oct 3 | 150 d | 5b |
| Campo | Apr 29 | Oct 13 | 167 d | 6b |
| Canon City | May 4 | Oct 7 | 156 d | 6a |
| Capulin | Jun 6 | Sep 15 | 101 d | 5a |
| Carbondale | May 31 | Sep 23 | 115 d | 6a |
| Carr | May 13 | Sep 27 | 137 d | 5b |
| Cascade | Jun 3 | Sep 17 | 106 d | 5b |
| Castle Rock | May 9 | Oct 2 | 146 d | 5b |
| Cedaredge | May 3 | Oct 9 | 159 d | 5b |
| Center | May 24 | Sep 24 | 123 d | 5a |
| Central City | Jun 5 | Sep 16 | 103 d | 5b |
| Chama | May 31 | Sep 23 | 115 d | 5b |
| Cheraw | Apr 30 | Oct 10 | 163 d | 6a |
| Cheyenne Wells | May 1 | Oct 14 | 166 d | 6a |
| Chromo | Jun 9 | Sep 22 | 105 d | 5b |
| Cimarron | Jun 20 | Sep 10 | 82 d | 5b |
| Clark | Jun 9 | Sep 12 | 95 d | 5a |
| Clifton | Apr 23 | Oct 20 | 180 d | 7a |
| Climax | frost any month | 5a | ||
| Coal Creek | May 4 | Oct 7 | 156 d | 6a |
| Coaldale | May 29 | Sep 20 | 114 d | 5b |
| Coalmont | frost any month | 4b | ||
| Collbran | May 17 | Sep 30 | 136 d | 6a |
| Colorado City | May 5 | Oct 10 | 158 d | 6a |
| Colorado Springs | May 3 | Oct 8 | 158 d | 6a |
| Commerce City | May 4 | Oct 8 | 157 d | 6a |
| Como | Jun 16 | Sep 9 | 85 d | 5a |
| Conejos | May 28 | Sep 21 | 116 d | 5a |
| Conifer | May 23 | Sep 22 | 122 d | 5b |
| Cope | May 3 | Oct 9 | 159 d | 5b |
| Cortez | May 12 | Oct 7 | 148 d | 7a |
| Cory | May 1 | Oct 7 | 159 d | 6b |
| Cotopaxi | Jun 11 | Sep 9 | 90 d | 5b |
| Cowdrey | frost any month | 4b | ||
| Craig | Jun 6 | Sep 12 | 98 d | 4a |
| Crawford | May 23 | Oct 1 | 131 d | 6a |
| Creede | frost any month | 5a | ||
| Crested Butte | frost any month | 5a | ||
| Crestone | May 26 | Sep 26 | 123 d | 5a |
| Cripple Creek | May 26 | Sep 26 | 123 d | 5b |
| Crook | May 11 | Oct 4 | 146 d | 5b |
| Crowley | May 2 | Oct 8 | 159 d | 5b |