Madison, WI 53785 Frost Dates
53785, near Madison, WI: the frost window
Around 05/01 is the usual last spring frost, about 246 days away. Fall's first freeze usually shows up around 10/09, roughly 161 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Madison in Zone 5b (-15 to -10°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
Madison's growing season runs out in roughly 6 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
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/17 and only about 1 year in 10 sees frost after that.
Madison against the rest of the dataset
About 161 days separate Madison's last and first frost, putting it 31,918 of 40,283 ZIP codes nationally. Within WI, it ranks 300 of 860.
Learn more
Two guides worth reading on 53785: zone vs. frost date, on why Zone 5b and Madison's frost date answer different questions, and the frost range, on how to read the range around Madison's dates instead of trusting one.