Sanford, ME 03830 Frost Dates
03830, near Sanford, ME: the frost window
Around 05/14 is the usual last spring frost, about 259 days away. Fall's first freeze usually shows up around 09/30, roughly 136 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Sanford in Zone 5b (-15 to -10°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
Sanford's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/14 isn't a guarantee
05/14 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/03 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/28 and only about 1 year in 10 sees frost after that.
Sanford against the rest of the dataset
Sanford's growing season runs about 136 days, ranking 37,627 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 389 of 456.
Learn more
Two guides worth reading on 03830: zone vs. frost date, on why Zone 5b and Sanford's frost date answer different questions, and the frost range, on how to read the range around Sanford's dates instead of trusting one.