Fitchburg, MA 01431 Frost Dates
01431, near Fitchburg, MA: the frost window
Around 05/01 is the usual last spring frost, about 246 days away. Fall's first freeze usually shows up around 10/09, roughly 162 days after the last spring frost.
Zone 6a (-10 to -5°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Fitchburg, not a forecast for this year.
Stretching the season past the first frost
Fitchburg'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.
How much risk comes with planting early here
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/19 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/14 and only about 1 year in 10 sees frost after that.
Fitchburg against the rest of the dataset
About 162 days separate Fitchburg's last and first frost, putting it 31,622 of 40,283 ZIP codes nationally. Within MA, it ranks 460 of 712.
Learn more
Two guides worth reading on 01431: the frost range, on how to read the range around Fitchburg's dates instead of trusting one, and local microclimates, on what one yard in Fitchburg can differ from the 01431 normal.