Haswell, CO 81045 Frost Dates
Frost dates for Haswell, CO, ZIP 81045
The last spring frost here typically falls around 04/30, about 245 days from today. The first fall frost typically arrives around 10/13, about 165 frost-free days later.
The USDA Plant Hardiness Zone Map puts Haswell in Zone 5b (-15 to -10°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 5b around Haswell has about 7 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.
How much risk comes with planting early here
04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 and you're betting against frost in roughly 9 years out of 10. 05/12 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Haswell compares
Haswell's growing season runs about 165 days, ranking 30,787 of 40,283 US ZIP codes measured here, longest to shortest. Within CO, it ranks 65 of 624.
Learn more
the frost range explains how to read the range around Haswell's dates instead of trusting one, and local microclimates explains what one yard in Haswell can differ from the 81045 normal.