Roscommon, MI 48630 Frost Dates
When can you plant in Roscommon, MI?
Around 05/20 is the usual last spring frost, about 265 days away. The first fall frost typically arrives around 10/01, about 136 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 5 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 05/20 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. 06/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Roscommon compares
Roscommon's growing season runs about 136 days, ranking 37,725 of 40,283 US ZIP codes measured here, longest to shortest. Within MI, it ranks 953 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 48630 normal.