Jamestown, CO 80310 Frost Dates
When can you plant in Jamestown, CO?
Around 05/06 is the usual last spring frost, about 251 days away. The first fall frost typically arrives around 10/05, about 151 frost-free days later.
The USDA Plant Hardiness Zone Map puts Jamestown in Zone 6a (-10 to -5°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 5 weeks of growing season left in Jamestown before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Jamestown's last frost
05/06 is the middle of 30 years of NOAA records, not a promise. Plant by 04/24 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Jamestown compares
At roughly 151 frost-free days, Jamestown places 35,171 of 40,283 ZIP codes in this dataset. Within CO, it ranks 318 of 624.
Learn more
the frost range covers how to read the range around Jamestown's dates instead of trusting one. local microclimates covers what one yard in Jamestown can differ from the 80310 normal.