Plant Hardiness Zones When selecting plants for the landscape, is important to select plants that will grow in your climate. The United States has 10 of growing or climate zones. These zones range from the zone 1 in the extreme northern part of United States, to his own 10, which covers the southernmost part. Zone 1, is for the most hardiest of cold weather plants. Temperatures in zone 1 can reach 50 degrees below 0. Zone 10 on the other hand, is is a more tropical climate. Zone 10 plants only need to worry about cold temperatures of 30 to 40 degrees. Your local nursery or garden center should have plants that are appropriate for your climate zone. however, if you are buying your seeds or plants over the Internet and, or through a catalog, you need to know which climate zone you live in. For example southern Florida, extreme southern Texas, and parts of California, are in Zone 10. the rest of Florida, parts of Louisiana, Texas, and much of California, or in zone 9. Zone 8 c ... Read more »