Lamoni, IA 50140 Frost Dates
Frost dates for Lamoni, IA, ZIP 50140
The last spring frost here typically falls around 04/17, about 232 days from today. The first fall frost typically arrives around 10/21, about 184 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 Lamoni, not a forecast for this year.
What to do before the first frost
Zone 5b around Lamoni has about 8 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
04/17 is the middle of 30 years of NOAA records, not a promise. Plant by 04/04 and you're betting against frost in roughly 9 years out of 10. 05/01 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lamoni compares
At roughly 184 frost-free days, Lamoni places 23,571 of 40,283 ZIP codes in this dataset. Within IA, it ranks 71 of 1,042.
Learn more
zone vs. frost date explains why Zone 5b and Lamoni's frost date answer different questions, and the frost range explains how to read the range around Lamoni's dates instead of trusting one.