Rolette, ND 58366 Frost Dates
Rolette, ND: when does the frost end?
The last spring frost here typically falls around 05/22, about 267 days from today. Fall's first freeze usually shows up around 09/20, roughly 120 days after the last spring frost.
Zone 3b (-35 to -30°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 Rolette, not a forecast for this year.
Stretching the season past the first frost
With roughly 3 weeks until Rolette's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/22 isn't a guarantee
05/22 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/10 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/03 and only about 1 year in 10 sees frost after that.
Rolette against the rest of the dataset
Rolette's growing season runs about 120 days, ranking 39,096 of 40,283 US ZIP codes measured here, longest to shortest. Within ND, it ranks 391 of 405.
Learn more
Before leaning on 58366's figures: the frost range explains how to read the range around Rolette's dates instead of trusting one, while local microclimates explains what one yard in Rolette can differ from the 58366 normal.