Interactive USDA Gardening and Plant Hardiness Zone Map for Colorado

Based on the 1990 USDA Hardiness Zone Map, this interactive version covers the state of Colorado which ranges from USDA Zone 2b to USDA Zone 7a.

USDA Zone 2b

-45°F to -40°F

USDA Zone 3a

-40°F to -35°F

USDA Zone 3b

-35°F to -30°F

USDA Zone 4a

-30°F to -25°F

USDA Zone 4b

-25°F to -20°F

USDA Zone 5a

-20°F to -15°F

USDA Zone 5b

-15°F to -10°F

USDA Zone 6a

-10°F to -5°F

USDA Zone 6b

-5°F to 0°F

USDA Zone 7a

0°F to 5°F

What are Hardiness Zones, Gardening Zones, Growing Zones and Plant Zones?

Hardiness Zones, Gardening Zones, Growing Zones and Plant Zones refer to defined geographic regions that can support specific plants, flowers and trees. The zones define a minimum range of temperatures that a plant or tree can survive safely in that zone. The most commonly used Hardiness Zones were defined by the USDA. The USDA provides a hard copy map that displays these zone throughout the US. The last update to this map covers minimum temperatures from 1961 to 1990. In 2012 the USDA released an updated Colorado hardiness zone map covering the period of 1981-2010