Riverside, IA 52327 Frost Dates
Frost dates for Riverside, IA, ZIP 52327
Typically, the last spring freeze lands around 04/29, roughly 244 days out. The first fall frost typically arrives around 10/09, about 162 frost-free days later.
The USDA Plant Hardiness Zone Map puts Riverside in Zone 5b (-15 to -10°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
Zone 5b around Riverside 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.
How much risk comes with planting early here
04/29 is the middle of 30 years of NOAA records, not a promise. Plant by 04/14 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 Riverside compares
About 162 days separate Riverside's last and first frost, putting it 31,797 of 40,283 ZIP codes nationally. Within IA, it ranks 709 of 1,042.
Learn more
zone vs. frost date explains why Zone 5b and Riverside's frost date answer different questions, and the frost range explains how to read the range around Riverside's dates instead of trusting one.