FrostDateCheck

Aurora, CO 80017 Frost Dates

When can you plant in Aurora, CO?

Zone 6a

Around 05/07 is the usual last spring frost, about 252 days away. The first fall frost typically arrives around 10/08, about 152 frost-free days later.

Zone 6a (-10 to -5°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 Aurora, not a forecast for this year.

What to do before the first frost

About 6 weeks of growing season left in Aurora before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 05/07 isn't a guarantee

05/07 is the middle of 30 years of NOAA records, not a promise. Plant by 04/26 and you're betting against frost in roughly 9 years out of 10. 05/21 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Aurora compares

At roughly 152 frost-free days, Aurora places 34,667 of 40,283 ZIP codes in this dataset. Within CO, it ranks 285 of 624.

Learn more

zone vs. frost date covers why Zone 6a and Aurora's frost date answer different questions. the frost range covers how to read the range around Aurora's dates instead of trusting one.