Grand Haven, MI 49429 Frost Dates
49429, near Grand Haven, MI: the frost window
The last spring frost here typically falls around 04/30, about 245 days from today. Fall's first freeze usually shows up around 10/24, roughly 175 days after the last spring frost.
Zone 6a (-10 to -5°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Grand Haven, not a forecast for this year.
Stretching the season past the first frost
Grand Haven's growing season runs out in roughly 8 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/30 isn't a guarantee
04/30 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/16 and only about 1 year in 10 sees frost after that.
Grand Haven against the rest of the dataset
Grand Haven's growing season runs about 175 days, ranking 26,800 of 40,283 US ZIP codes measured here, longest to shortest. Within MI, it ranks 139 of 1,153.
Learn more
Two guides worth reading on 49429: the frost range, on how to read the range around Grand Haven's dates instead of trusting one, and local microclimates, on what one yard in Grand Haven can differ from the 49429 normal.