Crystal Falls, MI 49881 Frost Dates
49881, near Crystal Falls, MI: the frost window
Typically, the last spring freeze lands around 05/24, roughly 269 days out. Fall's first freeze usually shows up around 09/25, roughly 121 days after the last spring frost.
Crystal Falls sits in USDA Zone 4b (-25 to -20°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.
Stretching the season past the first frost
Crystal Falls's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/24 isn't a guarantee
05/24 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/09 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/08 and only about 1 year in 10 sees frost after that.
Crystal Falls against the rest of the dataset
Crystal Falls's growing season runs about 121 days, ranking 39,016 of 40,283 US ZIP codes measured here, longest to shortest. Within MI, it ranks 1,094 of 1,153.
Learn more
Two guides worth reading on 49881: the frost range, on how to read the range around Crystal Falls's dates instead of trusting one, and local microclimates, on what one yard in Crystal Falls can differ from the 49881 normal.