Tulsa, OK 74104 Frost Dates
74104, near Tulsa, OK: the frost window
Typically, the last spring freeze lands around 03/31, roughly 215 days out. Fall's first freeze usually shows up around 11/04, roughly 220 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Tulsa in Zone 7b (5 to 10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Tulsa's growing season runs out in roughly 10 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 03/31 isn't a guarantee
03/31 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/15 and only about 1 year in 10 sees frost after that.
Tulsa against the rest of the dataset
Tulsa's growing season runs about 220 days, ranking 12,658 of 40,283 US ZIP codes measured here, longest to shortest. Within OK, it ranks 143 of 764.
Learn more
Two guides worth reading on 74104: the frost range, on how to read the range around Tulsa's dates instead of trusting one, and local microclimates, on what one yard in Tulsa can differ from the 74104 normal.