Mapleton, MN 56065 Frost Dates
Mapleton, MN: when does the frost end?
Around 04/30 is the usual last spring frost, about 245 days away. Fall's first freeze usually shows up around 10/07, roughly 161 days after the last spring frost.
Mapleton 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
With roughly 6 weeks until Mapleton's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/30 isn't a guarantee
04/30 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/12 and only about 1 year in 10 sees frost after that.
Mapleton against the rest of the dataset
Mapleton's growing season runs about 161 days, ranking 32,076 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 203 of 943.
Learn more
Before leaning on 56065's figures: zone vs. frost date explains why Zone 5a and Mapleton's frost date answer different questions, while the frost range explains how to read the range around Mapleton's dates instead of trusting one.