FrostDateCheck

Ashton, IA 51232 Frost Dates

Frost dates for Ashton, IA, ZIP 51232

Zone 5a

Around 05/05 is the usual last spring frost, about 250 days away. The first fall frost typically arrives around 10/03, about 152 frost-free days later.

The USDA Plant Hardiness Zone Map puts Ashton in Zone 5a (-20 to -15°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 5a around Ashton has about 5 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 Ashton's last frost

05/05 is the middle of 30 years of NOAA records, not a promise. Plant by 04/22 and you're betting against frost in roughly 9 years out of 10. 05/17 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Ashton compares

About 152 days separate Ashton's last and first frost, putting it 34,873 of 40,283 ZIP codes nationally. Within IA, it ranks 955 of 1,042.

Learn more

local microclimates explains what one yard in Ashton can differ from the 51232 normal, and zone vs. frost date explains why Zone 5a and Ashton's frost date answer different questions.