Simla, CO 80835 Frost Dates
When can you plant in Simla, CO?
The last spring frost here typically falls around 05/12, about 257 days from today. The first fall frost typically arrives around 10/02, about 141 frost-free days later.
Simla 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 5 weeks of growing season left in Simla 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
05/12 is the middle of 30 years of NOAA records, not a promise. Plant by 05/01 and you're betting against frost in roughly 9 years out of 10. 05/26 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Simla compares
At roughly 141 frost-free days, Simla places 36,959 of 40,283 ZIP codes in this dataset. Within CO, it ranks 402 of 624.
Learn more
local microclimates covers what one yard in Simla can differ from the 80835 normal. zone vs. frost date covers why Zone 5b and Simla's frost date answer different questions.