Berlin, NH 04226 Frost Dates
Frost dates for Berlin, NH, ZIP 04226
Typically, the last spring freeze lands around 05/19, roughly 264 days out. The first fall frost typically arrives around 09/25, about 129 frost-free days later.
Zone 5a (-20 to -15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Berlin, not a forecast for this year.
What to do before the first frost
Zone 5a around Berlin has about 4 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 05/19 isn't a guarantee
05/19 is the middle of 30 years of NOAA records, not a promise. Plant by 05/05 and you're betting against frost in roughly 9 years out of 10. 06/01 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Berlin compares
Berlin's growing season runs about 129 days, ranking 38,444 of 40,283 US ZIP codes measured here, longest to shortest. Within NH, it ranks 234 of 260.
Learn more
zone vs. frost date explains why Zone 5a and Berlin's frost date answer different questions, and the frost range explains how to read the range around Berlin's dates instead of trusting one.