Casselton, ND 58125 Frost Dates
Casselton, ND: when does the frost end?
The last spring frost here typically falls around 05/09, about 254 days from today. Fall's first freeze usually shows up around 10/01, roughly 143 days after the last spring frost.
Zone 4a (-30 to -25°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 Casselton, not a forecast for this year.
Stretching the season past the first frost
With roughly 5 weeks until Casselton's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/09 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/25 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/21 and only about 1 year in 10 sees frost after that.
Casselton against the rest of the dataset
Casselton's growing season runs about 143 days, ranking 36,543 of 40,283 US ZIP codes measured here, longest to shortest. Within ND, it ranks 86 of 405.
Learn more
Before leaning on 58125's figures: zone vs. frost date explains why Zone 4a and Casselton's frost date answer different questions, while the frost range explains how to read the range around Casselton's dates instead of trusting one.