USDA Zones

Zone Hardiness

Calculate Your Zone

Enter your zip code in the search box below, then click the location dot to view more information and the zone. Here is a demonstration (refresh the page if you need to restart the demo):
View a Demo of Finding Your Zone
Map courtesy of planthardiness.ars.usda.gov

The United States Department of Agriculture (USDA) has devised a system to provide gardeners with a basic guide to plant hardiness – how much winter cold a plant can withstand. The Hardiness Zone Map system divides the United States and Canada into numbered zones based on lowest average winter temperature. Even within a zone, different micro-climates exist, such as large urban areas which may be warmer or land situated at different elevations.

ZoneTemp (F)
1below -50
2-50 to -40
3-40 to -30
4-30 to -20
5-20 to -10
6-10 to 0
70 to 10
810 to 20
920 to 30
1030 to 40
11above 40
USDA growing zone map

What Affects Plant Hardiness?

The Hardiness Zone Map is a valuable tool but it is not foolproof. There are a variety of factors that can influence the hardiness of a given plant in a garden. These factors include: soil type, drainage, snow cover, exposure to wind, winter, rainfall (or lack of), as well as fluctuations in temperature.