Gibson, IA 50104 Frost Dates
Frost dates for Gibson, IA, ZIP 50104
The last spring frost here typically falls around 04/21, about 236 days from today. The first fall frost typically arrives around 10/16, about 176 frost-free days later.
Zone 5b (-15 to -10°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 Gibson, not a forecast for this year.
What to do before the first frost
Zone 5b around Gibson has about 7 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
04/21 is the middle of 30 years of NOAA records, not a promise. Plant by 04/08 and you're betting against frost in roughly 9 years out of 10. 05/04 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Gibson compares
Gibson's growing season runs about 176 days, ranking 26,683 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 166 of 1,042.
Learn more
local microclimates explains what one yard in Gibson can differ from the 50104 normal, and zone vs. frost date explains why Zone 5b and Gibson's frost date answer different questions.