Doon, IA 51235 Frost Dates
When can you plant in Doon, IA?
The last spring frost here typically falls around 05/01, about 246 days from today. The first fall frost typically arrives around 10/04, about 156 frost-free days later.
The USDA Plant Hardiness Zone Map puts Doon in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 5 weeks of growing season left in Doon before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/01 isn't a guarantee
05/01 is the middle of 30 years of NOAA records, not a promise. Plant by 04/18 and you're betting against frost in roughly 9 years out of 10. 05/13 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Doon compares
Doon's growing season runs about 156 days, ranking 33,769 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 864 of 1,042.
Learn more
the frost range covers how to read the range around Doon's dates instead of trusting one. local microclimates covers what one yard in Doon can differ from the 51235 normal.