Arriba, CO 80740 Frost Dates
When can you plant in Arriba, CO?
Around 05/15 is the usual last spring frost, about 260 days away. The first fall frost typically arrives around 10/02, about 139 frost-free days later.
Zone 5b (-15 to -10°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 Arriba, not a forecast for this year.
What to do before the first frost
About 5 weeks of growing season left in Arriba before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
05/15 is the middle of 30 years of NOAA records, not a promise. Plant by 05/02 and you're betting against frost in roughly 9 years out of 10. 05/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Arriba compares
About 139 days separate Arriba's last and first frost, putting it 37,285 of 40,283 ZIP codes nationally. Within CO, it ranks 406 of 624.
Learn more
local microclimates covers what one yard in Arriba can differ from the 80740 normal. zone vs. frost date covers why Zone 5b and Arriba's frost date answer different questions.