San Luis, CO 81126 Frost Dates
When can you plant in San Luis, CO?
The last spring frost here typically falls around 05/28, about 273 days from today. The first fall frost typically arrives around 09/21, about 115 frost-free days later.
San Luis sits in USDA Zone 5b (-15 to -10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 3 weeks of growing season left in San Luis 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
05/28 is the middle of 30 years of NOAA records, not a promise. Plant by 05/13 and you're betting against frost in roughly 9 years out of 10. 06/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How San Luis compares
At roughly 115 frost-free days, San Luis places 39,329 of 40,283 ZIP codes in this dataset. Within CO, it ranks 483 of 624.
Learn more
local microclimates covers what one yard in San Luis can differ from the 81126 normal. zone vs. frost date covers why Zone 5b and San Luis's frost date answer different questions.