Marlborough, MA 02238 Frost Dates
02238, near Marlborough, MA: the frost window
The last spring frost here typically falls around 05/02, about 247 days from today. Fall's first freeze usually shows up around 10/06, roughly 156 days after the last spring frost.
Marlborough sits in USDA Zone 6b (-5 to 0°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
Marlborough'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.
The actual range around Marlborough's last frost
05/02 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/22 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/16 and only about 1 year in 10 sees frost after that.
Marlborough against the rest of the dataset
At roughly 156 frost-free days, Marlborough places 33,533 of 40,283 ZIP codes in this dataset. Within MA, it ranks 633 of 712.
Learn more
Two guides worth reading on 02238: local microclimates, on what one yard in Marlborough can differ from the 02238 normal, and zone vs. frost date, on why Zone 6b and Marlborough's frost date answer different questions.