FrostDateCheck

Lake Mills, WI 53551 Frost Dates

When can you plant in Lake Mills, WI?

Zone 5b

Typically, the last spring freeze lands around 04/29, roughly 244 days out. The first fall frost typically arrives around 10/14, about 167 frost-free days later.

Lake Mills sits in USDA Zone 5b (-15 to -10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.

What to do before the first frost

About 7 weeks of growing season left in Lake Mills before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 04/29 isn't a guarantee

04/29 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 and you're betting against frost in roughly 9 years out of 10. 05/13 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Lake Mills compares

Lake Mills's growing season runs about 167 days, ranking 29,943 of 40,283 US ZIP codes measured here, longest to shortest. Within WI, it ranks 159 of 860.

Learn more

local microclimates covers what one yard in Lake Mills can differ from the 53551 normal. zone vs. frost date covers why Zone 5b and Lake Mills's frost date answer different questions.