Bield:Farm
Frost dates · New Hampshire

New Hampshire frost dates,
county by county.

Last spring frost and first fall frost probability data for all 10 counties in New Hampshire, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.

Variation across New Hampshire

30 days separate the earliest and latest counties.

The median last spring frost in Strafford County is April 17 — 30 days earlier than Coos County at May 17. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.

By geography

New Hampshire counties on the map.

Each dot is a county. Click for full frost-date detail. Color shows last-spring-frost timing — sage = earliest, amber = latest.

ListMap
Coos County · Spring May 17 · Fall Sep 30 · 136-day seasonBelknap County · Spring Apr 17 · Fall Nov 1 · 198-day seasonCarroll County · Spring May 4 · Fall Oct 4 · 153-day seasonStrafford County · Spring Apr 17 · Fall Oct 23 · 189-day seasonSullivan County · Spring May 1 · Fall Oct 11 · 163-day seasonRockingham County · Spring Apr 24 · Fall Oct 15 · 174-day seasonHillsborough County · Spring Apr 20 · Fall Oct 16 · 179-day seasonCheshire County · Spring May 2 · Fall Oct 10 · 161-day seasonMerrimack County · Spring Apr 30 · Fall Oct 9 · 162-day seasonGrafton County · Spring Apr 30 · Fall Oct 20 · 173-day season
Last spring frostEarliestMedianLatest
10 counties · click any county for full frost data
Alphabetical

All New Hampshire counties — A to Z.

Frost dates set the calendar. Bield: Farm runs it.

Pair these dates with live forecasts for your specific farm location. Bield: Farm logs your soil tests, planting dates, weather, and yield outcomes year over year.

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