Irvine, CA 90721 Frost Dates
When can you plant in Irvine, CA?
Around 01/05 is the usual last spring frost, about 130 days away. 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.
The actual range around Irvine's last frost
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
At roughly 365 frost-free days, Irvine places 245 of 40,283 ZIP codes in this dataset. Within CA, it ranks 40 of 2,555.
Learn more
local microclimates covers what one yard in Irvine can differ from the 90721 normal. zone vs. frost date covers why Zone 10a and Irvine's frost date answer different questions.