New Hampshire frost dates: P
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Pelham | May 3 | Oct 8 | 158 d | 6a |
| Peterborough | May 5 | Oct 6 | 154 d | 6a |
| Piermont | May 15 | Sep 28 | 136 d | 5a |
| Pike | May 15 | Sep 28 | 136 d | 5a |
| Pittsburg | May 25 | Sep 24 | 122 d | 4a |
| Pittsfield | May 8 | Oct 3 | 148 d | 5b |
| Plainfield | May 9 | Oct 6 | 150 d | 5a |
| Plaistow | May 1 | Oct 12 | 164 d | 6a |
| Plymouth | May 20 | Sep 27 | 130 d | 5b |
| Portsmouth | May 4 | Oct 8 | 157 d | 6a |