What Growing Zone Is New Hampshire In?
USDA hardiness zones
4a to 6a
2023 USDA Plant Hardiness Zone Map
New Hampshire spans USDA hardiness zone 4a to 6a across its major population centers, according to the 2023 USDA Plant Hardiness Zone Map. That's a real range, not a single number: where you fall in it depends on where in the state you actually are.
Find your exact zone
Your USDA hardiness zone
Zone 6b
Avg. annual minimum (°F)
-5°F to 0°F
Avg. annual minimum (°C)
-21°C to -18°C
Nearest reference point: Chicago, IL
This is a regional estimate based on the nearest of 826 reference points, each matched to the official 2023 USDA zone map. It’s accurate to within about a half-zone across most of the country, but elevation shifts zones over short distances, so if you’re in mountainous terrain, check the official USDA map for your exact address (see Sources below).
New Hampshire's USDA Hardiness Zones
Here's how the zone shifts across New Hampshire's major cities:
For your exact zone by ZIP code, use the Hardiness Zone Finder, and for what a zone number actually measures (and doesn't), see how zones actually work.
Frost Dates in New Hampshire
Frost dates track zone, so they shift across New Hampshire the same way the zone number does:
- North Country (Colebrook, Berlin) (zone 4): average last frost Apr 23 - May 7, average first frost Sep 23 - Oct 7.
- Southern New Hampshire (Manchester, Laconia) (zone 6): average last frost Mar 29 - Apr 12, average first frost Oct 18 - Nov 1.
These are averages, not guarantees. For your specific frost window, use the Frost Date Calculator. For a full vegetable-by-vegetable planting calendar already calculated from New Hampshire's frost dates, see the New Hampshire Planting Calendar.
New Hampshire's North Country, near Mt. Washington and Colebrook, runs several zones colder than the state's southern tier around Concord and Portsmouth, per NOAA's State Climate Summary for New Hampshire.
What Grows Well in New Hampshire's Zones
A few real, zone-appropriate picks recommended by University of New Hampshire Extension for New Hampshire landscapes: not an exhaustive list, but a genuine starting point.
- River birch (Betula nigra)
- Eastern redbud (Cercis canadensis)
- Black Hills spruce (Picea glauca 'Densata')
- Winterberry (Ilex verticillata)
- Witherod viburnum (Viburnum cassinoides)
- Koreanspice viburnum (Viburnum carlesii)
Ready to find your exact zone? Use the Hardiness Zone Finder: enter your ZIP code for a precise match against the 2023 USDA map.
New Hampshire Growing Zone FAQ
What growing zone is New Hampshire in?
New Hampshire spans USDA hardiness zones 4a to 6a on the 2023 USDA Plant Hardiness Zone Map. Colebrook is zone 4a and Berlin is zone 4b; enter your ZIP code in the Hardiness Zone Finder for your exact zone.
What growing zone is Colebrook, NH?
Colebrook is in USDA hardiness zone 4a on the 2023 USDA map. Zones within a city can differ by half a zone, so check your ZIP code for an exact match.
What growing zone is Berlin, NH?
Berlin is in USDA hardiness zone 4b on the 2023 USDA map. Zones within a city can differ by half a zone, so check your ZIP code for an exact match.
What growing zone is Concord, NH?
Concord is in USDA hardiness zone 5b on the 2023 USDA map. Zones within a city can differ by half a zone, so check your ZIP code for an exact match.
What growing zone is Manchester, NH?
Manchester is in USDA hardiness zone 6a on the 2023 USDA map. Zones within a city can differ by half a zone, so check your ZIP code for an exact match.
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The Spacing & Planting Cheat Sheet
When to start, when to plant, how far apart.
Sources & further reading
Zone and city data checked against the official USDA Plant Hardiness Zone Map. Plant recommendations sourced from University of New Hampshire Extension. Climate note sourced from NOAA State Climate Summaries. For more on how we build and verify reference data across this site, see our methodology page.
Growing zones in nearby states
Gardening near a state line? Zones don't stop at the border:
Or browse all 51 state growing-zone guides.