North Branch, MN 55056 Frost Dates
Frost dates for North Branch, MN, ZIP 55056
Around 05/19 is the usual last spring frost, about 264 days away. The first fall frost typically arrives around 09/25, about 128 frost-free days later.
Zone 4b (-25 to -20°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 North Branch, not a forecast for this year.
What to do before the first frost
Zone 4b around North Branch has about 4 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.
Why 05/19 isn't a guarantee
05/19 is the middle of 30 years of NOAA records, not a promise. Plant by 05/02 and you're betting against frost in roughly 9 years out of 10. 06/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How North Branch compares
At roughly 128 frost-free days, North Branch places 38,530 of 40,283 ZIP codes in this dataset. Within MN, it ranks 873 of 943.
Learn more
zone vs. frost date explains why Zone 4b and North Branch's frost date answer different questions, and the frost range explains how to read the range around North Branch's dates instead of trusting one.