Berlin, NH 04237 Frost Dates
When can you plant in Berlin, NH?
Around 05/12 is the usual last spring frost, about 257 days away. The first fall frost typically arrives around 09/29, about 139 frost-free days later.
Berlin sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 5 weeks of growing season left in Berlin before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Berlin's last frost
05/12 is the middle of 30 years of NOAA records, not a promise. Plant by 04/30 and you're betting against frost in roughly 9 years out of 10. 05/27 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Berlin compares
About 139 days separate Berlin's last and first frost, putting it 37,215 of 40,283 ZIP codes nationally. Within NH, it ranks 185 of 260.
Learn more
local microclimates covers what one yard in Berlin can differ from the 04237 normal. zone vs. frost date covers why Zone 5a and Berlin's frost date answer different questions.