FrostDateCheck

Thousand Oaks, CA 91320 Frost Dates

When can you plant in Thousand Oaks, CA?

Zone 10a

Around 12/31 is the usual last spring frost, about 125 days away. The first fall frost typically arrives around 12/28, about 365 frost-free days later.

The USDA Plant Hardiness Zone Map puts Thousand Oaks 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 Thousand Oaks before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

The actual range around Thousand Oaks's last frost

12/31 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. 12/11 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Thousand Oaks compares

Thousand Oaks's growing season runs about 365 days, ranking 428 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 166 of 2,555.

Learn more

zone vs. frost date covers why Zone 10a and Thousand Oaks's frost date answer different questions. the frost range covers how to read the range around Thousand Oaks's dates instead of trusting one.