Cass Lake, MN 56633 Frost Dates
When can you plant in Cass Lake, MN?
Typically, the last spring freeze lands around 05/17, roughly 262 days out. The first fall frost typically arrives around 09/26, about 131 frost-free days later.
The USDA Plant Hardiness Zone Map puts Cass Lake in Zone 3b (-35 to -30°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 4 weeks of growing season left in Cass Lake before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Cass Lake's last frost
05/17 is the middle of 30 years of NOAA records, not a promise. Plant by 05/03 and you're betting against frost in roughly 9 years out of 10. 05/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Cass Lake compares
Cass Lake's growing season runs about 131 days, ranking 38,316 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 835 of 943.
Learn more
the frost range covers how to read the range around Cass Lake's dates instead of trusting one. local microclimates covers what one yard in Cass Lake can differ from the 56633 normal.