FrostDateCheck

Roscommon, MI 48627 Frost Dates

When can you plant in Roscommon, MI?

Zone 5a

Typically, the last spring freeze lands around 05/19, roughly 264 days out. The first fall frost typically arrives around 09/23, about 125 frost-free days later.

The USDA Plant Hardiness Zone Map puts Roscommon in Zone 5a (-20 to -15°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

About 4 weeks of growing season left in Roscommon before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 05/19 isn't a guarantee

05/19 is the middle of 30 years of NOAA records, not a promise. Plant by 04/30 and you're betting against frost in roughly 9 years out of 10. 06/03 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Roscommon compares

At roughly 125 frost-free days, Roscommon places 38,773 of 40,283 ZIP codes in this dataset. Within MI, it ranks 1,075 of 1,153.

Learn more

the frost range covers how to read the range around Roscommon's dates instead of trusting one. local microclimates covers what one yard in Roscommon can differ from the 48627 normal.