Cottonwood, MN 56229 Frost Dates
56229, near Cottonwood, MN: the frost window
The last spring frost here typically falls around 05/05, about 250 days from today. Fall's first freeze usually shows up around 10/03, roughly 150 days after the last spring frost.
Cottonwood sits in USDA Zone 5a (-20 to -15°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
Cottonwood'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 04/21 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/18 and only about 1 year in 10 sees frost after that.
Cottonwood against the rest of the dataset
At roughly 150 frost-free days, Cottonwood places 35,339 of 40,283 ZIP codes in this dataset. Within MN, it ranks 526 of 943.
Learn more
Two guides worth reading on 56229: zone vs. frost date, on why Zone 5a and Cottonwood's frost date answer different questions, and the frost range, on how to read the range around Cottonwood's dates instead of trusting one.