Maine frost dates: M
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Machias | May 3 | Oct 9 | 159 d | 5b |
| Machiasport | May 3 | Oct 9 | 159 d | 6a |
| Madawaska | May 6 | Oct 2 | 149 d | 4b |
| Madison | May 8 | Oct 5 | 150 d | 5a |
| Manchester | Apr 27 | Oct 16 | 172 d | 5b |
| Mapleton | May 14 | Sep 26 | 135 d | 4a |
| Mars Hill | May 25 | Sep 18 | 116 d | 4a |
| Matinicus | Apr 27 | Oct 25 | 181 d | 7a |
| Mattawamkeag | May 4 | Oct 6 | 155 d | 5a |
| Mechanic Falls | May 3 | Oct 7 | 157 d | 5b |
| Meddybemps | Apr 21 | Oct 26 | 188 d | 5b |
| Medway | May 17 | Sep 29 | 135 d | 5a |
| Mexico | May 4 | Oct 6 | 155 d | 5a |
| Milbridge | May 3 | Oct 9 | 159 d | 6a |
| Milford | May 1 | Oct 6 | 158 d | 5a |
| Millinocket | May 9 | Oct 5 | 149 d | 5a |
| Milo | May 12 | Oct 1 | 142 d | 5a |
| Minot | Apr 25 | Oct 19 | 177 d | 5b |
| Monhegan | Apr 27 | Oct 25 | 181 d | 6b |
| Monmouth | May 1 | Oct 11 | 163 d | 5b |
| Monroe | May 7 | Oct 5 | 151 d | 5a |
| Monson | May 7 | Oct 9 | 155 d | 5a |
| Monticello | May 19 | Sep 23 | 127 d | 4a |
| Moody | May 1 | Oct 14 | 166 d | 6a |
| Morrill | May 7 | Oct 5 | 151 d | 5b |
| Mount Desert | Apr 27 | Oct 22 | 178 d | 6a |
| Mount Vernon | May 11 | Sep 29 | 141 d | 5b |