River Rouge, MI 48209 Frost Dates
When can you plant in River Rouge, MI?
Typically, the last spring freeze lands around 04/27, roughly 242 days out. The first fall frost typically arrives around 10/25, about 181 frost-free days later.
River Rouge sits in USDA Zone 6b (-5 to 0°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 8 weeks of growing season left in River Rouge before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
04/27 is the middle of 30 years of NOAA records, not a promise. Plant by 04/12 and you're betting against frost in roughly 9 years out of 10. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How River Rouge compares
About 181 days separate River Rouge's last and first frost, putting it 24,496 of 40,283 ZIP codes nationally. Within MI, it ranks 81 of 1,153.
Learn more
local microclimates covers what one yard in River Rouge can differ from the 48209 normal. zone vs. frost date covers why Zone 6b and River Rouge's frost date answer different questions.