If you've ever looked at the back of a seed packet or an instruction tag on a tree and seen a map of the United States divided into brightly colored bands, then you may already know about planting zones. The United States Department of Agriculture (USDA) has divided North America into 11 separate plant hardiness zones based on the lowest average winter temperature. Each zone differs in temperature by about 10 degrees. By following planting directions based on planting zones, gardeners are likely to choose plants that do well in their area.
Consult the USDA Plant Hardiness Zone Map to find the hardiness zone where you live and garden.
Locate the care information on the backs of seed packets and on stakes, stickers or tags attached to nursery plants.
Note the plant hardiness rating for each seed variety and/or plant.
Select plants that are rated to your hardiness zone. Plants that are rated for zones lower than your own may not survive the heat of summer. Plants that are rated for zones higher than your own may not survive the cold of winter. Plants that are rated for your zone should survive all temperature extremes in your area.