Arco, MN 56113 Frost Dates
When can you plant in Arco, MN?
The last spring frost here typically falls around 05/05, about 250 days from today. The first fall frost typically arrives around 10/03, about 150 frost-free days later.
Arco sits in USDA Zone 5a (-20 to -15°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 5 weeks of growing season left in Arco before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/05 isn't a guarantee
05/05 is the middle of 30 years of NOAA records, not a promise. Plant by 04/21 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Arco compares
Arco's growing season runs about 150 days, ranking 35,457 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 554 of 943.
Learn more
zone vs. frost date covers why Zone 5a and Arco's frost date answer different questions. the frost range covers how to read the range around Arco's dates instead of trusting one.