USDA Plant Hardiness Zone Map

   The USDA has come out with a new Plant Hardiness Zone Map. It now contains 13 zones. They are based on a 10° F window for the average cold temperature during winter.  See the USDA news release here for more info. If you want to go directly to the interactive map, you can find the map here. For those living near me, we're in Zone 5a.