Michigan frost dates: I
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Ida | Apr 27 | Oct 21 | 177 d | 6a |
| Idlewild | May 13 | Oct 2 | 142 d | 5b |
| Imlay City | May 4 | Oct 14 | 163 d | 6a |
| Indian River | May 31 | Sep 18 | 110 d | 4b |
| Ingalls | May 22 | Sep 27 | 128 d | 5a |
| Inkster | May 1 | Oct 15 | 167 d | 6b |
| Interlochen | May 9 | Oct 15 | 159 d | 6a |
| Ionia | May 3 | Oct 12 | 162 d | 6a |
| Iron Mountain | May 25 | Sep 24 | 122 d | 4b |
| Iron River | Jun 4 | Sep 10 | 98 d | 4a |
| Irons | May 28 | Sep 25 | 120 d | 5b |
| Ironwood | May 19 | Sep 28 | 132 d | 4b |
| Ishpeming | May 26 | Sep 25 | 122 d | 4b |
| Ithaca | May 1 | Oct 13 | 165 d | 6a |