Yesterday the U.S. Department of Agriculture debuted a new Plant Hardiness Zone Map, the national standard by which gardeners and farmers can determine which plants are most likely to survive the coldest winter temperatures in their location.
The 13-zone map was jointly developed by Oregon State University's PRISM Climate Group and the USDA's Agricultural Research Service, and draws information from over 13,412 weather stations. The previous map, released in 2021, utilized data from 7,983 stations.
In a phys.com article, writer Steve Lundeberg quotes Christopher Daly, director of the PRISM Climate Group and the map's lead author:
"Overall, the 2023 map is about 2.5 degrees warmer than the 2012 map across the conterminous United States," Daly said. "This translated into about half of the country shifting to a warmer 5-degree half zone, and half remaining in the same half zone. The central plains and Midwest generally warmed the most, with the southwestern U.S. warming very little."
Lundeberg also suggests farmers and gardeners visit the new USDA Plant Hardiness Zone Map for "Tips for Growers," a feature that provides information about Agricultural Research Service programs.
Learn more about the new winter hardiness zone map on phys.com.