9 Planting zones in Colorado with Map

There are 9 Planting zones in Colorado from Zone 3b to Zone 7b, as per the latest USDA data. A planting zone in Colorado refers to a geographical area defined by USDA on basis of average annual minimum winter temperatures.

Each zone represents a 5°F range of average annual minimum winter temperatures, therefore providing a crucial guidance in selection of plants that can withstand the local climate and successfully grow in different parts of the state.

Find your specific USDA planting zone in Colorado using one of two methods below: our ZIP code search tool or our interactive city-based Colorado planting zone map

Search Colorado Planting Zones by ZipCode

Planting Zones Colorado Map

Select your Colorado city from selection box below. Use the top right corner button in the map to switch map layers on/off.

What are the 9 planting zones in Colorado?

Colorado’s diverse topography results into 9 types of planting zones, from the coldest 3b to the warmest 7b.

1. Zone 3b

This zone, represented by the darkest purple colored areas on our map, is the coldest in Colorado with average annual minimum temperatures ranging from -35°F to -30°F (-37.2°C to -34.4°C). It covers small, isolated pockets in the highest elevations of the Rocky Mountains. This zone includes some of the state’s highest alpine areas.

2. Zone 4a

Shown in slightly lighter purple color on our map, Zone 4a experiences temperatures from -30°F to -25°F (-34.4°C to -31.7°C). This zone covers larger areas of the high mountains, including parts of the central Rockies. Some of the cities in this zone include some parts of Craig and Hartsel, representing some of Colorado’s coldest inhabited areas.

3. Zone 4b

The blue-purple colored areas on our map, Zone 4b has average minimum temperatures from -25°F to -20°F (-31.7°C to -28.9°C). This zone covers more of the mountainous regions, including areas around Steamboat Springs, Silverthorne, and Walden. It also includes Alamosa in the San Luis Valley, showcasing the cold temperatures of high-altitude valleys.

4. Zone 5a

Represented in teal color on our map given above, Zone 5a covers significant portions of Colorado’s mountain regions and some high plains, with temperatures ranging from -20°F to -15°F (-28.9°C to -26.1°C). This zone includes many popular mountain towns such as Aspen, Breckenridge, some parts of Vail, and Estes Park, as well as parts of the northern Front Range near Greeley.

5. Zone 5b

Shown in light teal color on our map, Zone 5b is one of the most extensive zones in Colorado, covering large parts of the Front Range and mountain valleys. With temperatures from -15°F to -10°F (-26.1°C to -23.3°C), this zone have cities like Fort Collins, Castle Rock, and parts of Colorado Springs, representing a transition between mountain and plains climates.

6. Zone 6a

The dark green color areas on our map shown above is Zone 6a, it covers much of the lower elevations of the Front Range and western valleys, with temperatures ranging from -10°F to -5°F (-23.3°C to -20.6°C). This zone includes major population centers like Denver, Pueblo, and parts of Grand Junction, as well as many Front Range suburbs.

7. Zone 6b

Shown in green on the map, Zone 6b represents some of the warmer areas of Colorado, with temperatures from -5°F to 0°F (-20.6°C to -17.8°C). This zone is primarily found in the western and southwestern parts of the state, including cities like Durango, Montrose, and Delta, as well as parts of the Eastern Plains.

8. Zone 7a

Represented by light green areas on map, Zone 7a is one of the warmest zones in Colorado, with temperatures ranging from 0°F to 5°F (-17.8°C to -15°C). This zone is mainly found in the lower elevations of the Western Slope, including parts of Grand Junction, Fruita, and Cortez, representing some of Colorado’s mildest winter climates.

9. Zone 7b

The warmest zone in Colorado, 7b, is shown in yellow color on our map and experiences minimum temperatures from 5°F to 10°F (-15°C to -12.2°C). While not extensively represented on the map, small pockets of this zone exist in the lowest elevations of the Western Slope, including microclimates around Grand Junction and other protected valley areas.

Planting Zones in Colorado with Cities

USDA Planting zones for Colorado cities, towns and counties. Data source: USDA.

Planting Zones in Colorado	Temp Range (°F)	Cities
6a	-10 to -5	Aguilar, Arapahoe, Arvada, Aurora, Avon, Avondale, Basalt, Bayfield, Bennett, Bethune, Beulah, Boncarbo, Boone, Boulder, Branson, Brighton, Broomfield, Burlington, Canon City, Carbondale, Cheraw, Cheyenne Wells, Coal Creek, Collbran, Colorado City, Colorado Springs, Commerce City, Crawford, Denver, Dinosaur, Dolores, Dupont, Durango, Eads, Eldorado Springs, Englewood, Florence, Fort Lyon, Fountain, Fowler, Gardner, Glenwood Springs, Golden, Granada, Hartman, Hasty, Hesperus, Hoehne, Holly, Hygiene, Idalia, Ignacio, Kim, La Junta, La Veta, Lafayette, Lamar, Las Animas, Littleton, Longmont, Louisville, Mancos, Manzanola, Marvel, Maybell, Mc Clave, Model, Montrose, New Castle, Norwood, Nucla, Olney Springs, Parachute, Penrose, Poncha Springs, Pueblo, Rangely, Ridgway, Rifle, Rockvale, Rocky Ford, Rye, Sheridan Lake, Silt, Snowmass, Somerset, Stratton, Swink, Trinchera, Trinidad, Vona, Walsenburg, Watkins, Westminster, Weston, Wetmore, Wheat Ridge, Whitewater, Wild Horse, Wiley, Wolcott, Yoder
5b	-15 to -10	Agate, Akron, Allenspark, Amherst, Anton, Antonito, Arlington, Arriba, Atwood, Bailey, Bellvue, Berthoud, Black Hawk, Bond, Brighton, Brush, Buena Vista, Buffalo Creek, Burns, Byers, Calhan, Carr, Cascade, Castle Rock, Cedaredge, Central City, Chama, Chromo, Cimarron, Coaldale, Colorado Springs, Conifer, Cope, Cotopaxi, Cripple Creek, Crook, Crowley, Dacono, Deer Trail, Del Norte, Dinosaur, Divide, Drake, Dumont, Eagle, Eckley, Edwards, Elbert, Elizabeth, Erie, Estes Park, Evans, Evergreen, Fairplay, Firestone, Flagler, Fleming, Fort Collins, Fort Garland, Fort Lupton, Fort Morgan, Franktown, Fraser, Frederick, Genoa, Glen Haven, Golden, Grant, Greeley, Green Mountain Falls, Guffey, Gunnison, Gypsum, Hamilton, Haswell, Haxtun, Henderson, Hillrose, Hillside, Holyoke, Hot Sulphur Springs, Howard, Hudson, Hugo, Idaho Springs, Idledale, Iliff, Indian Hills, Jamestown, Joes, Johnstown, Julesburg, Karval, Keenesburg, Kiowa, Kirk, Kit Carson, Kittredge, La Jara, Lake George, Laporte, Larkspur, Limon, Lindon, Littleton, Livermore, Longmont, Louviers, Loveland, Lyons, Manitou Springs, Masonville, Matheson, Mc Coy, Mead, Meeker, Merino, Milliken, Moffat, Molina, Monarch, Monument, Morrison, Nathrop, Nederland, Ophir, Ordway, Otis, Ouray, Ovid, Padroni, Pagosa Springs, Palmer Lake, Paoli, Parker, Peetz, Peyton, Pierce, Pine, Pinecliffe, Placerville, Platteville, Powderhorn, Pueblo, Ramah, Rico, Roggen, Rollinsville, Rush, Saguache, Salida, San Luis, Sargents, Sedalia, Sedgwick, Seibert, Severance, Shawnee, Simla, Slater, Snowmass Village, Snyder, South Fork, Steamboat Springs, Sterling, Stoneham, Strasburg, Sugar City, Tabernash, Telluride, Timnath, U S A F Academy, Vail, Vernon, Victor, Villa Grove, Ward, Wellington, Westcliffe, Windsor, Woodland Park, Woodrow, Woody Creek, Wray, Yuma
5a	-20 to -15	Alma, Almont, Aspen, Ault, Blanca, Breckenridge, Briggsdale, Capulin, Center, Clark, Climax, Como, Conejos, Craig, Creede, Crested Butte, Crestone, Dillon, Eaton, Empire, Estes Park, Florissant, Frisco, Galeton, Georgetown, Gilcrest, Gill, Granby, Grand Lake, Granite, Greeley, Grover, Hayden, Hereford, Hooper, Jaroso, Jefferson, Kersey, Kremmling, La Salle, Lake City, Leadville, Manassa, Meredith, Minturn, Monte Vista, Mosca, New Raymer, Nunn, Oak Creek, Ohio City, Orchard, Parshall, Phippsburg, Pitkin, Red Cliff, Red Feather Lakes, Romeo, Sanford, Silver Plume, Silverthorne, Silverton, Toponas, Twin Lakes, Vail, Weldona, Wiggins, Winter Park, Woodland Park, Yampa
4b	-25 to -20	Alamosa, Coalmont, Cowdrey, Homelake, Parlin, Rand, Silverthorne, Steamboat Springs, Walden
4a	-30 to -25	Craig, Hartsel
6b	-5 to 0	Arboles, Austin, Battlement Mesa, Bedrock, Cahone, Campo, Cory, De Beque, Delta, Dove Creek, Durango, Eckert, Egnar, Gateway, Glade Park, Grand Junction, Hotchkiss, Lazear, Lewis, Loma, Mesa, Montrose, Naturita, Olathe, Paonia, Paradox, Pleasant View, Pritchett, Redvale, Springfield, Two Buttes, Vilas, Walsh, Yellow Jacket
7a	0 to 5	Clifton, Cortez, Fruita, Grand Junction, Mack, Mesa Verde National Park, Palisade, Towaoc

What scientific data was utilized in creating Colorado’s new planting zones?

The new USDA Plant Hardiness Zone Map for Colorado is developed by the PRISM Climate Group at Oregon State University using scientific algorithms that interpolate temperature data, accounting for factors such as elevation, topography, and proximity to bodies of water. This generated the high-resolution planting zones map that capture Colorado’s diverse climate conditions, from its mountainous regions to its plains and plateaus, with scientific accuracy.