Porterville, CA 93257 Frost Dates
When can you plant in Porterville, CA?
Typically, the last spring freeze lands around 02/20, roughly 176 days out. The first fall frost typically arrives around 11/30, about 284 frost-free days later.
Porterville sits in USDA Zone 9b (25 to 30°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 13 weeks of growing season left in Porterville before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Porterville's last frost
02/20 is the middle of 30 years of NOAA records, not a promise. Plant by 01/20 and you're betting against frost in roughly 9 years out of 10. 03/26 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Porterville compares
Porterville's growing season runs about 284 days, ranking 4,671 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,728 of 2,555.
Learn more
the frost range covers how to read the range around Porterville's dates instead of trusting one. local microclimates covers what one yard in Porterville can differ from the 93257 normal.