| City | Population | Last spring frost | First fall frost | Growing season | Zone |
|---|---|---|---|---|---|
| Portland | 69,911 | Apr 26 | Oct 15 | 170 days | 6a |
| Lewiston | 38,866 | Apr 25 | Oct 19 | 177 days | 5b |
| Bangor | 32,518 | May 4 | Oct 4 | 152 days | 5a |
| South Portland | 27,007 | Apr 26 | Oct 15 | 170 days | 6a |
| Auburn | 25,441 | Apr 25 | Oct 19 | 177 days | 5b |
| Sanford | 22,663 | May 16 | Sep 30 | 136 days | 5b |
| Biddeford | 22,399 | May 9 | Oct 3 | 146 days | 6a |
| Westbrook | 21,565 | Apr 26 | Oct 15 | 170 days | 5b |
| Saco | 21,159 | Apr 26 | Oct 15 | 170 days | 6a |
| Augusta | 19,155 | Apr 27 | Oct 16 | 172 days | 5b |
| Waterville | 17,579 | May 2 | Oct 10 | 159 days | 5b |
| Brewer | 9,636 | May 4 | Oct 4 | 152 days | 5a |
| Ellsworth | 8,862 | May 8 | Oct 9 | 152 days | 5b |
| Bath | 8,835 | May 10 | Oct 6 | 149 days | 6a |
| Presque Isle | 8,694 | May 14 | Sep 26 | 131 days | 4a |
| Old Town | 7,589 | May 13 | Sep 28 | 137 days | 5a |
| Caribou | 7,321 | May 7 | Oct 1 | 143 days | 4a |
| Rockland | 7,142 | Apr 27 | Oct 19 | 175 days | 6a |
| Belfast | 6,988 | May 7 | Oct 5 | 151 days | 5b |
| Gardiner | 6,206 | May 1 | Oct 11 | 163 days | 5b |