Irvine, CA 92781 Frost Dates
When can you plant in Irvine, CA?
Typically, the last spring freeze lands around 01/05, roughly 130 days out. The first fall frost typically arrives around 12/25, about 365 frost-free days later.
The USDA Plant Hardiness Zone Map puts Irvine in Zone 10a (30 to 35°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 17 weeks of growing season left in Irvine 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
01/05 is the middle of 30 years of NOAA records, not a promise. Plant by 02/02 and you're betting against frost in roughly 9 years out of 10. 12/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Irvine compares
About 365 days separate Irvine's last and first frost, putting it 271 of 40,283 ZIP codes nationally. Within CA, it ranks 66 of 2,555.
Learn more
local microclimates covers what one yard in Irvine can differ from the 92781 normal. zone vs. frost date covers why Zone 10a and Irvine's frost date answer different questions.