US Grow Zones

New Hampshire planting zones & frost dates

Last updated

The 2 New Hampshire cities on this site fall in zone 6a. Last spring frost dates range from May 4 in Manchester to May 4 in Nashua.

CityZoneLast frostFirst frostPopulation
Manchester6aMay 4Oct 6116,386
Nashua6aMay 4Oct 591,851

Frost dates are 30%-risk dates from the nearest suitable NOAA station. Population: Census Vintage 2024 estimates.