Rancho Santa Margarita, CA 92693 Frost Dates
92693, near Rancho Santa Margarita, CA: the frost window
Around 01/06 is the usual last spring frost, about 131 days away. Fall's first freeze usually shows up around 01/02, roughly 365 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Rancho Santa Margarita in Zone 10b (35 to 40°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Rancho Santa Margarita's growing season runs out in roughly 18 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 01/06 isn't a guarantee
01/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/13 and only about 1 year in 10 sees frost after that.
Rancho Santa Margarita against the rest of the dataset
About 365 days separate Rancho Santa Margarita's last and first frost, putting it 911 of 40,283 ZIP codes nationally. Within CA, it ranks 375 of 2,555.
Learn more
Two guides worth reading on 92693: local microclimates, on what one yard in Rancho Santa Margarita can differ from the 92693 normal, and zone vs. frost date, on why Zone 10b and Rancho Santa Margarita's frost date answer different questions.