Glidden, IA 51443 Frost Dates
Frost dates for Glidden, IA, ZIP 51443
Typically, the last spring freeze lands around 04/26, roughly 241 days out. The first fall frost typically arrives around 10/09, about 164 frost-free days later.
Zone 5a (-20 to -15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Glidden, not a forecast for this year.
What to do before the first frost
Zone 5a around Glidden 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
04/26 is the middle of 30 years of NOAA records, not a promise. Plant by 04/12 and you're betting against frost in roughly 9 years out of 10. 05/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Glidden compares
At roughly 164 frost-free days, Glidden places 31,045 of 40,283 ZIP codes in this dataset. Within IA, it ranks 600 of 1,042.
Learn more
zone vs. frost date explains why Zone 5a and Glidden's frost date answer different questions, and the frost range explains how to read the range around Glidden's dates instead of trusting one.