Marlborough, MA 01888 Frost Dates
Marlborough, MA: when does the frost end?
Around 05/02 is the usual last spring frost, about 247 days away. 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
With roughly 6 weeks until Marlborough's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/02 isn't a guarantee
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
About 156 days separate Marlborough's last and first frost, putting it 33,530 of 40,283 ZIP codes nationally. Within MA, it ranks 630 of 712.
Learn more
Before leaning on 01888's figures: the frost range explains how to read the range around Marlborough's dates instead of trusting one, while local microclimates explains what one yard in Marlborough can differ from the 01888 normal.