Kirkman, IA 51447 Frost Dates
Frost dates for Kirkman, IA, ZIP 51447
Around 04/27 is the usual last spring frost, about 242 days away. The first fall frost typically arrives around 10/09, about 165 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 Kirkman, not a forecast for this year.
What to do before the first frost
Zone 5a around Kirkman 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.
Why 04/27 isn't a guarantee
04/27 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. 05/09 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Kirkman compares
About 165 days separate Kirkman's last and first frost, putting it 30,788 of 40,283 ZIP codes nationally. Within IA, it ranks 569 of 1,042.
Learn more
the frost range explains how to read the range around Kirkman's dates instead of trusting one, and local microclimates explains what one yard in Kirkman can differ from the 51447 normal.