Swisher, IA 52338 Frost Dates
Frost dates for Swisher, IA, ZIP 52338
Around 04/27 is the usual last spring frost, about 242 days away. The first fall frost typically arrives around 10/11, about 165 frost-free days later.
Swisher 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
Zone 5a around Swisher has about 6 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Swisher's last frost
04/27 is the middle of 30 years of NOAA records, not a promise. Plant by 04/13 and you're betting against frost in roughly 9 years out of 10. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Swisher compares
At roughly 165 frost-free days, Swisher places 30,645 of 40,283 ZIP codes in this dataset. Within IA, it ranks 517 of 1,042.
Learn more
zone vs. frost date explains why Zone 5a and Swisher's frost date answer different questions, and the frost range explains how to read the range around Swisher's dates instead of trusting one.