Rio Dell, CA 95554 Frost Dates
When can you plant in Rio Dell, CA?
The last spring frost here typically falls around 03/04, about 188 days from today. The first fall frost typically arrives around 11/22, about 264 frost-free days later.
Zone 9b (25 to 30°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 Rio Dell, not a forecast for this year.
What to do before the first frost
About 12 weeks of growing season left in Rio Dell before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 03/04 isn't a guarantee
03/04 is the middle of 30 years of NOAA records, not a promise. Plant by 01/27 and you're betting against frost in roughly 9 years out of 10. 04/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Rio Dell compares
At roughly 264 frost-free days, Rio Dell places 6,067 of 40,283 ZIP codes in this dataset. Within CA, it ranks 2,008 of 2,555.
Learn more
the frost range covers how to read the range around Rio Dell's dates instead of trusting one. local microclimates covers what one yard in Rio Dell can differ from the 95554 normal.