| City | Population | Last spring frost | First fall frost | Growing season | Zone |
|---|---|---|---|---|---|
| Bridgeport | 152,273 | Apr 5 | Nov 6 | 216 days | 7a |
| Stamford | 139,535 | Apr 17 | Oct 23 | 188 days | 7a |
| New Haven | 138,774 | Apr 17 | Oct 27 | 193 days | 7a |
| Hartford | 121,981 | Apr 17 | Oct 26 | 191 days | 6b |
| Waterbury | 115,771 | Apr 26 | Oct 16 | 175 days | 6b |
| Norwalk | 94,508 | Apr 17 | Oct 23 | 188 days | 7a |
| Danbury | 89,033 | May 1 | Oct 14 | 166 days | 6b |
| New Britain | 76,286 | Apr 17 | Oct 26 | 191 days | 6b |
| Bristol | 62,341 | Apr 25 | Oct 18 | 172 days | 6b |
| Meriden | 60,810 | Apr 26 | Oct 16 | 175 days | 6b |
| West Haven | 55,351 | Apr 17 | Oct 27 | 193 days | 7a |
| Milford | 51,215 | Apr 5 | Nov 6 | 216 days | 7a |
| Middletown | 48,439 | Apr 26 | Oct 16 | 175 days | 6b |
| Shelton | 42,880 | Apr 25 | Oct 17 | 175 days | 6b |
| Norwich | 40,001 | Apr 14 | Oct 24 | 192 days | 6b |
| Torrington | 35,796 | May 8 | Oct 5 | 151 days | 6a |
| Naugatuck | 32,230 | Apr 18 | Oct 26 | 191 days | 6b |
| New London | 28,003 | Apr 16 | Oct 28 | 194 days | 7a |
| Ansonia | 19,216 | Apr 25 | Oct 17 | 175 days | 6b |
| Derby | 12,925 | Apr 25 | Oct 17 | 175 days | 6b |
| Groton | 10,160 | Apr 16 | Oct 28 | 194 days | 7a |