What Is a Plant Hardiness Zone?

Your zone number, developed by the USDA, lets you know which plants will do best in your yard based on the climate you live in.

Before You Start Gardening

If you're just getting into gardening, first learn which U.S. Department of Agriculture (USDA) Plant Hardiness Zone you live in. Your zone number, developed by the USDA, lets you know which plants will do best in your yard based on the climate you live in.

What Your Zone Means

The USDA divided the country, and Puerto Rico, into 13 zones based on a location's annual minimum winter temperature. Zone 1, for instance, includes Fairbanks, Alaska, and the northern islands of Canada. Zone 11 includes most of Hawaii. Zones 12 and 13 are found in Puerto Rico. Each zone is further subdivided for better accuracy.

Planting in Your Zone

You'll find that most plants and seeds you buy will come with a label listing their Plant Hardiness Zones. To find out what zone you're in, view the USDA Plant Hardiness Zone map, which was updated by the USDA in 2012 to reflect weather data as recent as 2005.

Other Weather Factors to Consider

Keep in mind that you should consider several other factors in addition to your Hardiness Zone. These include the type of soil you're working with, altitude, moisture, humidity, heat and wind. If you live in a hot climate, consider purchasing a copy of the American Horticultural Society's Heat Zone Map. This map divides the country into 12 zones, which are based on the average number of days per year that a region experiences temperatures over 86 degrees F.

Going Native

Knowing your Plant Hardiness Zone is important, but it's easy to grow a vibrant and healthy garden by working with plants that are native to your region. Learn how with our article "Gardening with Native Plants."