Windsor, CO 80550 Frost Dates
When can you plant in Windsor, CO?
Around 05/03 is the usual last spring frost, about 248 days away. The first fall frost typically arrives around 10/06, about 154 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 Windsor, not a forecast for this year.
What to do before the first frost
About 6 weeks of growing season left in Windsor before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Windsor's last frost
05/03 is the middle of 30 years of NOAA records, not a promise. Plant by 04/21 and you're betting against frost in roughly 9 years out of 10. 05/15 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Windsor compares
About 154 days separate Windsor's last and first frost, putting it 34,207 of 40,283 ZIP codes nationally. Within CO, it ranks 262 of 624.
Learn more
the frost range covers how to read the range around Windsor's dates instead of trusting one. local microclimates covers what one yard in Windsor can differ from the 80550 normal.