Sioux City, IA 51103 Frost Dates
When can you plant in Sioux City, IA?
The last spring frost here typically falls around 04/29, about 244 days from today. The first fall frost typically arrives around 10/05, about 159 frost-free days later.
Sioux City 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.
What to do before the first frost
About 5 weeks of growing season left in Sioux City before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Sioux City's last frost
04/29 is the middle of 30 years of NOAA records, not a promise. Plant by 04/16 and you're betting against frost in roughly 9 years out of 10. 05/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Sioux City compares
At roughly 159 frost-free days, Sioux City places 32,573 of 40,283 ZIP codes in this dataset. Within IA, it ranks 771 of 1,042.
Learn more
zone vs. frost date covers why Zone 5a and Sioux City's frost date answer different questions. the frost range covers how to read the range around Sioux City's dates instead of trusting one.