Calumet, MN 55775 Frost Dates
55775, near Calumet, MN: the frost window
Around 05/17 is the usual last spring frost, about 262 days away. Fall's first freeze usually shows up around 09/24, roughly 130 days after the last spring frost.
Zone 4a (-30 to -25°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 Calumet, not a forecast for this year.
Stretching the season past the first frost
Calumet's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/17 isn't a guarantee
05/17 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 05/31 and only about 1 year in 10 sees frost after that.
Calumet against the rest of the dataset
About 130 days separate Calumet's last and first frost, putting it 38,410 of 40,283 ZIP codes nationally. Within MN, it ranks 855 of 943.
Learn more
Two guides worth reading on 55775: the frost range, on how to read the range around Calumet's dates instead of trusting one, and local microclimates, on what one yard in Calumet can differ from the 55775 normal.