Belfast, ME 04676 Frost Dates
Frost dates for Belfast, ME, ZIP 04676
Around 05/08 is the usual last spring frost, about 253 days away. The first fall frost typically arrives around 10/09, about 152 frost-free days later.
Belfast sits in USDA Zone 5b (-15 to -10°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
Zone 5b around Belfast has about 6 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 05/08 isn't a guarantee
05/08 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. 05/23 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Belfast compares
Belfast's growing season runs about 152 days, ranking 34,740 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 242 of 456.
Learn more
zone vs. frost date explains why Zone 5b and Belfast's frost date answer different questions, and the frost range explains how to read the range around Belfast's dates instead of trusting one.