2012 USDA Map Updated and Officially Released
After a good generation of waiting...the USDA Hardiness Zone Map was finally released today with updated winter average annual temperatures.
The new, legitimate/official USDA map is based on temperature data from 1976 to 2005. The previous map, from 1990, only used temperature data from 1974 to 1986.
You'll see slight changes of hardiness zones across the Carolinas -- mainly a tiny shift northward across counties. Areas around southern Charleston, SC are now easing into Zone 9a.
Here is a link that might be useful: Official 2012 USDA Hardiness Zone Map