FrostDateCheck

Rose City, MI 48647 Frost Dates

Frost dates for Rose City, MI, ZIP 48647

Zone 5a

The last spring frost here typically falls around 05/20, about 265 days from today. The first fall frost typically arrives around 10/01, about 133 frost-free days later.

Zone 5a (-20 to -15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Rose City, not a forecast for this year.

What to do before the first frost

Zone 5a around Rose City 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.

Why 05/20 isn't a guarantee

05/20 is the middle of 30 years of NOAA records, not a promise. Plant by 05/02 and you're betting against frost in roughly 9 years out of 10. 06/02 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Rose City compares

At roughly 133 frost-free days, Rose City places 38,089 of 40,283 ZIP codes in this dataset. Within MI, it ranks 1,006 of 1,153.

Learn more

zone vs. frost date explains why Zone 5a and Rose City's frost date answer different questions, and the frost range explains how to read the range around Rose City's dates instead of trusting one.