Patterson, IA 50218 Frost Dates
When can you plant in Patterson, IA?
Around 04/30 is the usual last spring frost, about 245 days away. The first fall frost typically arrives around 10/03, about 157 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 Patterson, not a forecast for this year.
What to do before the first frost
About 5 weeks of growing season left in Patterson before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
04/30 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. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Patterson compares
Patterson's growing season runs about 157 days, ranking 33,458 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 854 of 1,042.
Learn more
zone vs. frost date covers why Zone 5b and Patterson's frost date answer different questions. the frost range covers how to read the range around Patterson's dates instead of trusting one.