Rockville, SC 29487 Frost Dates
Rockville, SC: when does the frost end?
Around 03/01 is the usual last spring frost, about 185 days away. Fall's first freeze usually shows up around 12/06, roughly 280 days after the last spring frost.
Zone 9a (20 to 25°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 Rockville, not a forecast for this year.
Stretching the season past the first frost
With roughly 14 weeks until Rockville's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 03/01 isn't a guarantee
03/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/01 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/21 and only about 1 year in 10 sees frost after that.
Rockville against the rest of the dataset
At roughly 280 frost-free days, Rockville places 4,848 of 40,283 ZIP codes in this dataset. Within SC, it ranks 29 of 519.
Learn more
Before leaning on 29487's figures: zone vs. frost date explains why Zone 9a and Rockville's frost date answer different questions, while the frost range explains how to read the range around Rockville's dates instead of trusting one.