Del Norte, CO 81135 Frost Dates
Frost dates for Del Norte, CO, ZIP 81135
Around 05/23 is the usual last spring frost, about 268 days away. The first fall frost typically arrives around 09/25, about 123 frost-free days later.
The USDA Plant Hardiness Zone Map puts Del Norte in Zone 4b (-25 to -20°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
Zone 4b around Del Norte has about 4 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 05/23 isn't a guarantee
05/23 is the middle of 30 years of NOAA records, not a promise. Plant by 05/11 and you're betting against frost in roughly 9 years out of 10. 06/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Del Norte compares
Del Norte's growing season runs about 123 days, ranking 38,904 of 40,283 US ZIP codes measured here, longest to shortest. Within CO, it ranks 457 of 624.
Learn more
the frost range explains how to read the range around Del Norte's dates instead of trusting one, and local microclimates explains what one yard in Del Norte can differ from the 81135 normal.