Sergeant Bluff, IA 51111 Frost Dates
Frost dates for Sergeant Bluff, IA, ZIP 51111
The last spring frost here typically falls around 04/29, about 244 days from today. The first fall frost typically arrives around 10/05, about 159 frost-free days later.
Sergeant Bluff sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 5a around Sergeant Bluff 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.
Why 04/29 isn't a guarantee
04/29 is the middle of 30 years of NOAA records, not a promise. Plant by 04/16 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 Sergeant Bluff compares
At roughly 159 frost-free days, Sergeant Bluff places 32,643 of 40,283 ZIP codes in this dataset. Within IA, it ranks 780 of 1,042.
Learn more
the frost range explains how to read the range around Sergeant Bluff's dates instead of trusting one, and local microclimates explains what one yard in Sergeant Bluff can differ from the 51111 normal.