The United States is divided into 13 different plant hardiness zones, each with "A" and "B" subdivisions. This is a number assigned to a plant that tells you how cold of a temperature the plant can ...

Question: My husband bought a few plants at a nursery recently. There was a tag describing the USDA Climate Zone. I live in Sonoma 9a, but I saw other zones mentioned such as 9b and 10. There was also ...