Mizpah, MN 56660 Frost Dates
Mizpah, MN: when does the frost end?
Around 05/16 is the usual last spring frost, about 261 days away. Fall's first freeze usually shows up around 09/26, roughly 131 days after the last spring frost.
Zone 3b (-35 to -30°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 Mizpah, not a forecast for this year.
Stretching the season past the first frost
With roughly 4 weeks until Mizpah's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/16 isn't a guarantee
05/16 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 05/30 and only about 1 year in 10 sees frost after that.
Mizpah against the rest of the dataset
About 131 days separate Mizpah's last and first frost, putting it 38,347 of 40,283 ZIP codes nationally. Within MN, it ranks 841 of 943.
Learn more
Before leaning on 56660's figures: zone vs. frost date explains why Zone 3b and Mizpah's frost date answer different questions, while the frost range explains how to read the range around Mizpah's dates instead of trusting one.