Grand Rapids, MI 49505 Frost Dates
Grand Rapids, MI: when does the frost end?
Around 05/06 is the usual last spring frost, about 251 days away. Fall's first freeze usually shows up around 10/10, roughly 157 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 Rapids, not a forecast for this year.
Stretching the season past the first frost
With roughly 6 weeks until Grand Rapids's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Grand Rapids's last frost
05/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/23 and only about 1 year in 10 sees frost after that.
Grand Rapids against the rest of the dataset
Grand Rapids's growing season runs about 157 days, ranking 33,194 of 40,283 US ZIP codes measured here, longest to shortest. Within MI, it ranks 685 of 1,153.
Learn more
Before leaning on 49505's figures: the frost range explains how to read the range around Grand Rapids's dates instead of trusting one, while local microclimates explains what one yard in Grand Rapids can differ from the 49505 normal.