New hardiness zone map will help US gardeners keep pace with climate change

By CHRISTINA LARSON
AP Science Writer

WASHINGTON (AP) — The U.S. Department of Agriculture has updated its “plant hardiness zone map” for the first time in a decade. It shows that the lowest likely winter temperature in a given region is 2.5 degrees warmer than when the map was last published in 2012. The map is a reference guide for growers selecting appropriate seeds and starter plants. The shifts on the map are not even. For example, the Midwest warmed more than the Southeast.