Merton, WI 53056 Frost Dates
Frost dates for Merton, WI, ZIP 53056
The last spring frost here typically falls around 04/30, about 245 days from today. The first fall frost typically arrives around 10/16, about 167 frost-free days later.
The USDA Plant Hardiness Zone Map puts Merton in Zone 5b (-15 to -10°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 5b around Merton has about 7 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.
Why 04/30 isn't a guarantee
04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/16 and you're betting against frost in roughly 9 years out of 10. 05/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Merton compares
Merton's growing season runs about 167 days, ranking 29,977 of 40,283 US ZIP codes measured here, longest to shortest. Within WI, it ranks 162 of 860.
Learn more
zone vs. frost date explains why Zone 5b and Merton's frost date answer different questions, and the frost range explains how to read the range around Merton's dates instead of trusting one.