Armstrong, IA 50514 Frost Dates
When can you plant in Armstrong, IA?
Typically, the last spring freeze lands around 05/02, roughly 247 days out. The first fall frost typically arrives around 10/03, about 153 frost-free days later.
Armstrong 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
About 5 weeks of growing season left in Armstrong before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Armstrong's last frost
05/02 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. 05/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Armstrong compares
About 153 days separate Armstrong's last and first frost, putting it 34,573 of 40,283 ZIP codes nationally. Within IA, it ranks 924 of 1,042.
Learn more
local microclimates covers what one yard in Armstrong can differ from the 50514 normal. zone vs. frost date covers why Zone 5a and Armstrong's frost date answer different questions.