Backus, MN 56435 Frost Dates
56435, near Backus, MN: the frost window
Around 05/05 is the usual last spring frost, about 250 days away. Fall's first freeze usually shows up around 10/05, roughly 150 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Backus in Zone 4a (-30 to -25°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
Backus'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.
How much risk comes with planting early here
05/05 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/19 and only about 1 year in 10 sees frost after that.
Backus against the rest of the dataset
At roughly 150 frost-free days, Backus places 35,417 of 40,283 ZIP codes in this dataset. Within MN, it ranks 542 of 943.
Learn more
Two guides worth reading on 56435: local microclimates, on what one yard in Backus can differ from the 56435 normal, and zone vs. frost date, on why Zone 4a and Backus's frost date answer different questions.