Deer River, MN 56636 Frost Dates
Frost dates for Deer River, MN, ZIP 56636
Typically, the last spring freeze lands around 05/16, roughly 261 days out. The first fall frost typically arrives around 10/01, about 138 frost-free days later.
Deer River sits in USDA Zone 3b (-35 to -30°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
Zone 3b around Deer River has about 5 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.
How much risk comes with planting early here
05/16 is the middle of 30 years of NOAA records, not a promise. Plant by 05/01 and you're betting against frost in roughly 9 years out of 10. 05/31 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Deer River compares
About 138 days separate Deer River's last and first frost, putting it 37,422 of 40,283 ZIP codes nationally. Within MN, it ranks 769 of 943.
Learn more
local microclimates explains what one yard in Deer River can differ from the 56636 normal, and zone vs. frost date explains why Zone 3b and Deer River's frost date answer different questions.