USDA Plant Hardiness Zones
USA Garden Hub – Plant Hardiness Zone Finder
Understanding Plant Hardiness Zones
USDA Plant Hardiness Zones are geographic areas defined by their average annual minimum winter temperature. They help gardeners and growers determine which plants are most likely to thrive in their location. Each zone represents a 10°F temperature difference and is further divided into “a” and “b” subzones representing 5°F differences.
Why Hardiness Zones Matter
Choosing plants that match your hardiness zone ensures they can survive your region’s winter temperatures, leading to healthier plants and more successful gardens.
| Zone | Temperature Range (°F) | Example Regions |
|---|---|---|
| 1-3 | Below -40°F to -30°F | Alaska, Northern Minnesota |
| 4-5 | -30°F to -10°F | Montana, Wyoming, Northern New England |
| 6-7 | -10°F to 10°F | Mid-Atlantic, Southern Midwest |
| 8-9 | 10°F to 30°F | Southern US, Coastal California |
| 10-13 | 30°F and above | Southern Florida, Hawaii, Puerto Rico |
Find Your Zone
Don’t know your zone? Check the USDA Official Hardiness Zone Map to find your area.
Zone Subzones (a and b)
Each main zone (1–13) is split into “a” and “b” subzones for finer detail (5°F steps). For example, Zone 7a is 0°F to 5°F and Zone 7b is 5°F to 10°F.
Use your zone when choosing plants from our categories to ensure they will thrive in your garden.