Grand Haven, MI 49422 Frost Dates
Frost dates for Grand Haven, MI, ZIP 49422
Typically, the last spring freeze lands around 04/30, roughly 245 days out. The first fall frost typically arrives around 10/24, about 175 frost-free days later.
Zone 6b (-5 to 0°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.
What to do before the first frost
Zone 6b around Grand Haven has about 8 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 04/30 isn't a guarantee
04/30 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. 05/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Grand Haven compares
About 175 days separate Grand Haven's last and first frost, putting it 26,799 of 40,283 ZIP codes nationally. Within MI, it ranks 138 of 1,153.
Learn more
zone vs. frost date explains why Zone 6b and Grand Haven's frost date answer different questions, and the frost range explains how to read the range around Grand Haven's dates instead of trusting one.