New Hampshire planting zones & frost dates
USDA hardiness zones in New Hampshire go from 5a to 6a. Pick your city for its average frost dates and a planting calendar, or search by ZIP code.
| City | Zone | Avg. last frost | Avg. first frost |
|---|---|---|---|
| Bedford | 6a | Apr 21 | Oct 19 |
| Claremont | 5b | May 14 | Oct 1 |
| Concord | 5b | May 8 | Oct 3 |
| Derry | 6a | Apr 30 | Oct 11 |
| Derry Village | 6a | Apr 30 | Oct 11 |
| Dover | 6a | May 3 | Oct 10 |
| Durham | 6a | May 8 | Oct 4 |
| East Concord | 5b | May 8 | Oct 3 |
| Keene | 5b | May 14 | Oct 1 |
| Laconia | 5b | Apr 30 | Oct 18 |
| Lebanon | 5a | May 9 | Oct 6 |
| Londonderry | 6a | Apr 21 | Oct 19 |
| Manchester | 6a | Apr 30 | Oct 11 |
| Merrimack | 6a | Apr 30 | Oct 12 |
| Nashua | 6a | Apr 30 | Oct 12 |
| Pelham | 6a | May 3 | Oct 8 |
| Portsmouth | 6a | May 4 | Oct 8 |
| Rochester | 6a | Apr 30 | Oct 9 |
| Salem | 6a | Apr 21 | Oct 21 |
| Somersworth | 6a | Apr 30 | Oct 9 |
| Windham | 6a | May 3 | Oct 8 |
Cities with 10,000+ residents. Data: USDA Plant Hardiness Zone Map 2023 and NOAA Climate Normals 1991–2020. Sources and method.