Selby, SD 57472 Frost Dates
57472, near Selby, SD: the frost window
The last spring frost here typically falls around 05/08, about 253 days from today. Fall's first freeze usually shows up around 10/01, roughly 145 days after the last spring frost.
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 Selby, not a forecast for this year.
Stretching the season past the first frost
Selby's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Selby's last frost
05/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/26 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.
Selby against the rest of the dataset
Selby's growing season runs about 145 days, ranking 36,256 of 40,283 US ZIP codes measured here, longest to shortest. Within SD, it ranks 239 of 378.
Learn more
Two guides worth reading on 57472: the frost range, on how to read the range around Selby's dates instead of trusting one, and local microclimates, on what one yard in Selby can differ from the 57472 normal.