Old Town, ME 04487 Frost Dates
04487, near Old Town, ME: the frost window
Around 05/06 is the usual last spring frost, about 251 days away. Fall's first freeze usually shows up around 10/08, roughly 155 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Old Town in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Old Town's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/06 isn't a guarantee
05/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/26 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/18 and only about 1 year in 10 sees frost after that.
Old Town against the rest of the dataset
At roughly 155 frost-free days, Old Town places 33,945 of 40,283 ZIP codes in this dataset. Within ME, it ranks 201 of 456.
Learn more
Two guides worth reading on 04487: local microclimates, on what one yard in Old Town can differ from the 04487 normal, and zone vs. frost date, on why Zone 5a and Old Town's frost date answer different questions.