Castroville, TX 78009 Frost Dates
When can you plant in Castroville, TX?
Around 02/18 is the usual last spring frost, about 174 days away. The first fall frost typically arrives around 12/09, about 296 frost-free days later.
Castroville sits in USDA Zone 9a (20 to 25°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 15 weeks of growing season left in Castroville before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 02/18 isn't a guarantee
02/18 is the middle of 30 years of NOAA records, not a promise. Plant by 01/18 and you're betting against frost in roughly 9 years out of 10. 03/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Castroville compares
Castroville's growing season runs about 296 days, ranking 4,241 of 40,283 US ZIP codes measured here, longest to shortest. Within TX, it ranks 510 of 2,558.
Learn more
zone vs. frost date covers why Zone 9a and Castroville's frost date answer different questions. the frost range covers how to read the range around Castroville's dates instead of trusting one.