Menno, SD 57045 Frost Dates
57045, near Menno, SD: the frost window
Around 05/01 is the usual last spring frost, about 246 days away. Fall's first freeze usually shows up around 10/04, roughly 156 days after the last spring frost.
Menno sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Menno'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.
How much risk comes with planting early here
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/14 and only about 1 year in 10 sees frost after that.
Menno against the rest of the dataset
At roughly 156 frost-free days, Menno places 33,772 of 40,283 ZIP codes in this dataset. Within SD, it ranks 85 of 378.
Learn more
Two guides worth reading on 57045: local microclimates, on what one yard in Menno can differ from the 57045 normal, and zone vs. frost date, on why Zone 5a and Menno's frost date answer different questions.