Alma, MI 48801 Frost Dates
Frost dates for Alma, MI, ZIP 48801
Around 05/01 is the usual last spring frost, about 246 days away. The first fall frost typically arrives around 10/13, about 164 frost-free days later.
Alma sits in USDA Zone 6a (-10 to -5°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
Zone 6a around Alma 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 05/01 isn't a guarantee
05/01 is the middle of 30 years of NOAA records, not a promise. Plant by 04/17 and you're betting against frost in roughly 9 years out of 10. 05/19 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Alma compares
Alma's growing season runs about 164 days, ranking 30,881 of 40,283 US ZIP codes measured here, longest to shortest. Within MI, it ranks 473 of 1,153.
Learn more
zone vs. frost date explains why Zone 6a and Alma's frost date answer different questions, and the frost range explains how to read the range around Alma's dates instead of trusting one.