Berlin, NH 04231 Frost Dates
Frost dates for Berlin, NH, ZIP 04231
The last spring frost here typically falls around 05/06, about 251 days from today. The first fall frost typically arrives around 10/02, about 147 frost-free days later.
The USDA Plant Hardiness Zone Map puts Berlin in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 5a around Berlin has about 5 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 05/06 isn't a guarantee
05/06 is the middle of 30 years of NOAA records, not a promise. Plant by 04/27 and you're betting against frost in roughly 9 years out of 10. 05/19 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Berlin compares
At roughly 147 frost-free days, Berlin places 35,872 of 40,283 ZIP codes in this dataset. Within NH, it ranks 150 of 260.
Learn more
local microclimates explains what one yard in Berlin can differ from the 04231 normal, and zone vs. frost date explains why Zone 5a and Berlin's frost date answer different questions.