Minnesota frost dates: I
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Ihlen | May 4 | Oct 2 | 151 d | 4b |
| International Falls | May 29 | Sep 13 | 107 d | 3b |
| Inver Grove Heights | Apr 24 | Oct 16 | 175 d | 5a |
| Iona | May 7 | Sep 29 | 145 d | 5a |
| Iron | May 12 | Oct 1 | 142 d | 3b |
| Ironton | May 13 | Sep 27 | 137 d | 4a |
| Isabella | May 31 | Sep 15 | 107 d | 3b |
| Isanti | May 2 | Oct 4 | 155 d | 4b |
| Isle | May 10 | Oct 3 | 146 d | 4a |
| Ivanhoe | May 6 | Oct 3 | 150 d | 4b |