Black Earth, WI 53515 Frost Dates
Black Earth, WI: when does the frost end?
Around 05/07 is the usual last spring frost, about 252 days away. Fall's first freeze usually shows up around 10/01, roughly 148 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Black Earth in Zone 5a (-20 to -15°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
With roughly 5 weeks until Black Earth's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/07 isn't a guarantee
05/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/22 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/22 and only about 1 year in 10 sees frost after that.
Black Earth against the rest of the dataset
At roughly 148 frost-free days, Black Earth places 35,734 of 40,283 ZIP codes in this dataset. Within WI, it ranks 612 of 860.
Learn more
Before leaning on 53515's figures: the frost range explains how to read the range around Black Earth's dates instead of trusting one, while local microclimates explains what one yard in Black Earth can differ from the 53515 normal.