Humboldt, SD 57035 Frost Dates
When can you plant in Humboldt, SD?
The last spring frost here typically falls around 05/03, about 248 days from today. The first fall frost typically arrives around 10/04, about 153 frost-free days later.
Humboldt 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 Humboldt before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Humboldt's last frost
05/03 is the middle of 30 years of NOAA records, not a promise. Plant by 04/20 and you're betting against frost in roughly 9 years out of 10. 05/15 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Humboldt compares
At roughly 153 frost-free days, Humboldt places 34,593 of 40,283 ZIP codes in this dataset. Within SD, it ranks 116 of 378.
Learn more
zone vs. frost date covers why Zone 4b and Humboldt's frost date answer different questions. the frost range covers how to read the range around Humboldt's dates instead of trusting one.