Highland, CA 92321 Frost Dates
When can you plant in Highland, CA?
Typically, the last spring freeze lands around 05/05, roughly 250 days out. The first fall frost typically arrives around 11/02, about 176 frost-free days later.
Zone 8a (10 to 15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Highland, not a forecast for this year.
What to do before the first frost
About 9 weeks of growing season left in Highland before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Highland's last frost
05/05 is the middle of 30 years of NOAA records, not a promise. Plant by 04/09 and you're betting against frost in roughly 9 years out of 10. 05/31 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Highland compares
At roughly 176 frost-free days, Highland places 26,352 of 40,283 ZIP codes in this dataset. Within CA, it ranks 2,354 of 2,555.
Learn more
zone vs. frost date covers why Zone 8a and Highland's frost date answer different questions. the frost range covers how to read the range around Highland's dates instead of trusting one.