Belfast, ME 04986 Frost Dates
When can you plant in Belfast, ME?
Typically, the last spring freeze lands around 05/07, roughly 252 days out. The first fall frost typically arrives around 10/05, about 151 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 Belfast, not a forecast for this year.
What to do before the first frost
About 5 weeks of growing season left in Belfast before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/07 isn't a guarantee
05/07 is the middle of 30 years of NOAA records, not a promise. Plant by 04/28 and you're betting against frost in roughly 9 years out of 10. 05/21 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Belfast compares
Belfast's growing season runs about 151 days, ranking 35,001 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 273 of 456.
Learn more
local microclimates covers what one yard in Belfast can differ from the 04986 normal. zone vs. frost date covers why Zone 5a and Belfast's frost date answer different questions.