Custer, MI 49402 Frost Dates
Custer, MI: when does the frost end?
Around 05/17 is the usual last spring frost, about 262 days away. Fall's first freeze usually shows up around 10/07, roughly 144 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Custer in Zone 5b (-15 to -10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 6 weeks until Custer's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/17 isn't a guarantee
05/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/01 and only about 1 year in 10 sees frost after that.
Custer against the rest of the dataset
About 144 days separate Custer's last and first frost, putting it 36,459 of 40,283 ZIP codes nationally. Within MI, it ranks 885 of 1,153.
Learn more
Before leaning on 49402's figures: local microclimates explains what one yard in Custer can differ from the 49402 normal, while zone vs. frost date explains why Zone 5b and Custer's frost date answer different questions.