Hewitt, WI 54441 Frost Dates
Hewitt, WI: when does the frost end?
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 Hewitt in Zone 4b (-25 to -20°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 Hewitt's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/05 isn't a guarantee
05/05 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 05/20 and only about 1 year in 10 sees frost after that.
Hewitt against the rest of the dataset
Hewitt's growing season runs about 150 days, ranking 35,350 of 40,283 US ZIP codes measured here, longest to shortest. Within WI, it ranks 573 of 860.
Learn more
Before leaning on 54441's figures: the frost range explains how to read the range around Hewitt's dates instead of trusting one, while local microclimates explains what one yard in Hewitt can differ from the 54441 normal.