Dearborn, MI 48228 Frost Dates
48228, near Dearborn, MI: the frost window
The last spring frost here typically falls around 04/27, about 242 days from today. Fall's first freeze usually shows up around 10/25, roughly 181 days after the last spring frost.
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 Dearborn, not a forecast for this year.
Stretching the season past the first frost
Dearborn'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.
The actual range around Dearborn's last frost
04/27 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/11 and only about 1 year in 10 sees frost after that.
Dearborn against the rest of the dataset
About 181 days separate Dearborn's last and first frost, putting it 24,429 of 40,283 ZIP codes nationally. Within MI, it ranks 74 of 1,153.
Learn more
Two guides worth reading on 48228: the frost range, on how to read the range around Dearborn's dates instead of trusting one, and local microclimates, on what one yard in Dearborn can differ from the 48228 normal.