Vermillion, SD 57069 Frost Dates
57069, near Vermillion, SD: the frost window
Typically, the last spring freeze lands around 05/03, roughly 248 days out. Fall's first freeze usually shows up around 10/03, roughly 153 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Vermillion in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Vermillion'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.
Why 05/03 isn't a guarantee
05/03 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/20 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/16 and only about 1 year in 10 sees frost after that.
Vermillion against the rest of the dataset
About 153 days separate Vermillion's last and first frost, putting it 34,493 of 40,283 ZIP codes nationally. Within SD, it ranks 108 of 378.
Learn more
Two guides worth reading on 57069: the frost range, on how to read the range around Vermillion's dates instead of trusting one, and local microclimates, on what one yard in Vermillion can differ from the 57069 normal.