Postville, IA 52162 Frost Dates
When can you plant in Postville, IA?
The last spring frost here typically falls around 05/02, about 247 days from today. The first fall frost typically arrives around 10/11, about 161 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 Postville, not a forecast for this year.
What to do before the first frost
About 6 weeks of growing season left in Postville before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/02 isn't a guarantee
05/02 is the middle of 30 years of NOAA records, not a promise. Plant by 04/17 and you're betting against frost in roughly 9 years out of 10. 05/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Postville compares
At roughly 161 frost-free days, Postville places 32,059 of 40,283 ZIP codes in this dataset. Within IA, it ranks 747 of 1,042.
Learn more
local microclimates covers what one yard in Postville can differ from the 52162 normal. zone vs. frost date covers why Zone 5a and Postville's frost date answer different questions.