Lemmon, SD 57638 Frost Dates
When can you plant in Lemmon, SD?
Typically, the last spring freeze lands around 05/10, roughly 255 days out. The first fall frost typically arrives around 09/30, about 142 frost-free days later.
Lemmon sits in USDA Zone 4b (-25 to -20°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.
What to do before the first frost
About 5 weeks of growing season left in Lemmon 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
05/10 is the middle of 30 years of NOAA records, not a promise. Plant by 04/30 and you're betting against frost in roughly 9 years out of 10. 05/24 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lemmon compares
About 142 days separate Lemmon's last and first frost, putting it 36,766 of 40,283 ZIP codes nationally. Within SD, it ranks 285 of 378.
Learn more
zone vs. frost date covers why Zone 4b and Lemmon's frost date answer different questions. the frost range covers how to read the range around Lemmon's dates instead of trusting one.