Highmore, SD 57345 Frost Dates
When can you plant in Highmore, SD?
Typically, the last spring freeze lands around 05/12, roughly 257 days out. The first fall frost typically arrives around 10/01, about 142 frost-free days later.
The USDA Plant Hardiness Zone Map puts Highmore in Zone 4b (-25 to -20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 5 weeks of growing season left in Highmore before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
05/12 is the middle of 30 years of NOAA records, not a promise. Plant by 04/28 and you're betting against frost in roughly 9 years out of 10. 05/28 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Highmore compares
At roughly 142 frost-free days, Highmore places 36,786 of 40,283 ZIP codes in this dataset. Within SD, it ranks 286 of 378.
Learn more
zone vs. frost date covers why Zone 4b and Highmore's frost date answer different questions. the frost range covers how to read the range around Highmore's dates instead of trusting one.