Belfast, ME 04642 Frost Dates
Belfast, ME: when does the frost end?
Typically, the last spring freeze lands around 05/07, roughly 252 days out. Fall's first freeze usually shows up around 10/05, roughly 151 days after the last spring frost.
Belfast sits in USDA Zone 6a (-10 to -5°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.
Stretching the season past the first frost
With roughly 5 weeks until Belfast's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/21 and only about 1 year in 10 sees frost after that.
Belfast against the rest of the dataset
At roughly 151 frost-free days, Belfast places 34,986 of 40,283 ZIP codes in this dataset. Within ME, it ranks 258 of 456.
Learn more
Before leaning on 04642's figures: local microclimates explains what one yard in Belfast can differ from the 04642 normal, while zone vs. frost date explains why Zone 6a and Belfast's frost date answer different questions.