Hayden, CO 81639 Frost Dates
When can you plant in Hayden, CO?
Around 06/01 is the usual last spring frost, about 277 days away. The first fall frost typically arrives around 09/20, about 109 frost-free days later.
The USDA Plant Hardiness Zone Map puts Hayden 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 3 weeks of growing season left in Hayden before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 06/01 isn't a guarantee
06/01 is the middle of 30 years of NOAA records, not a promise. Plant by 05/15 and you're betting against frost in roughly 9 years out of 10. 06/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hayden compares
About 109 days separate Hayden's last and first frost, putting it 39,524 of 40,283 ZIP codes nationally. Within CO, it ranks 510 of 624.
Learn more
zone vs. frost date covers why Zone 5a and Hayden's frost date answer different questions. the frost range covers how to read the range around Hayden's dates instead of trusting one.