Frost Dates & Planting Calendars in New Hampshire
Typical last spring frost, first fall frost, and growing-season length for 24 cities in New Hampshire, based on NOAA 1991–2020 climate normals. Click a city for its full frost-date summary, monthly temperature chart, and 42-crop planting calendar.
| City | Last Spring Frost (typical) | First Fall Frost (typical) | Growing Season | USDA Zone |
|---|---|---|---|---|
| Manchester | April 30 | October 11 | 164 days | 6a |
| Nashua | April 30 | October 12 | 165 days | 6a |
| Concord | May 8 | October 3 | 146 days | 5b |
| East Concord | May 8 | October 3 | 146 days | 5b |
| Derry Village | April 30 | October 11 | 162 days | 6a |
| Dover | May 3 | October 10 | 158 days | 6a |
| Rochester | April 30 | October 9 | 161 days | 6a |
| Salem | April 21 | October 21 | 182 days | 6a |
| Merrimack | April 30 | October 12 | 165 days | 6a |
| Keene | May 14 | October 1 | 138 days | 5b |
| Derry | April 30 | October 11 | 162 days | 6a |
| Portsmouth | May 4 | October 8 | 157 days | 6a |
| Bedford | April 21 | October 19 | 180 days | 6a |
| Laconia | April 30 | October 18 | 170 days | 5b |
| Lebanon | May 9 | October 6 | 148 days | 5a |
| Windham | May 3 | October 8 | 156 days | 6a |
| Claremont | May 14 | October 1 | 140 days | 5b |
| Pelham | May 3 | October 8 | 156 days | 6a |
| Somersworth | April 30 | October 9 | 161 days | 6a |
| Londonderry | April 21 | October 19 | 180 days | 6a |
| Durham | May 8 | October 4 | 148 days | 6a |
| Hampton | May 4 | October 8 | 157 days | 6a |
| Berlin | May 14 | September 30 | 135 days | 4b |
| Exeter | May 4 | October 8 | 157 days | 6a |