Milltown, WI 54858 Frost Dates
Frost dates for Milltown, WI, ZIP 54858
Around 05/06 is the usual last spring frost, about 251 days away. The first fall frost typically arrives around 10/04, about 149 frost-free days later.
The USDA Plant Hardiness Zone Map puts Milltown in Zone 4b (-25 to -20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 4b around Milltown has about 5 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Milltown's last frost
05/06 is the middle of 30 years of NOAA records, not a promise. Plant by 04/23 and you're betting against frost in roughly 9 years out of 10. 05/20 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Milltown compares
At roughly 149 frost-free days, Milltown places 35,541 of 40,283 ZIP codes in this dataset. Within WI, it ranks 601 of 860.
Learn more
local microclimates explains what one yard in Milltown can differ from the 54858 normal, and zone vs. frost date explains why Zone 4b and Milltown's frost date answer different questions.