Landscaping and Climate Zones

If you are landscaping or gardening, understanding climate zones, also known as plant hardiness zones ,will help you select flowers, trees, and other plants that are more likely to thrive.

There’s more than one zone classification system. A common one used in North America is the USDA Climate Zones, where zones range from 1 to 11. In zone 1, temperatures can drop to minus 50 degrees Fahrenheit, while in zone 11 (Hawaii and extreme Southern Florida), temperatures rarely drop below 40 degrees Fahrenheit. When shopping online or in a catalog, you will see notations such as "zones 3-7" to indicate climate. Find worldwide climate information here.

Zone History

The first map created for planting information was the USDA Hardiness Zone Map. This map came from the combined effort of Henry Skinner in the 1800s (when he worked with the U.S. National Arboretum) and the American Horticultural Society.

This generalized map of meteorological information placed each area of the U.S. into a climate zone. It was the first time people had guidelines for planting and growing both decorative plants and crops. This was necessary because many people were moving across the country and didn’t know a local area’s growing capabilities.

The map was revised with more detailed information in 1960, expanded to include all of North America, and named the Plant Hardiness Zone Map. The map changed as a result of more technological ability to map weather trends, additional data, and changing weather patterns.

Zone Limitations

The hardiness zone map ,is helpful, but it’s only a general guideline. Other local factors affect how plants grow in your location. Situations such as smog or pollution, soil feasibility, or catastrophic conditions such as the eruption of a volcano can affect how or if your plants grow. You can probably get the best advice on plants for your location from local landscaping and gardening experts.