What Hardiness Zone Is Utah?
Utah spans USDA hardiness zones 4a–8b on the 2023 Plant Hardiness Zone Map. The most common zone is 6a, covering 32% of Utah's ZIP codes, followed by zone 7a (18%). Zone 6a means the coldest night of an average winter reaches −10°F to −5°F (−23°C to −21°C). Enter your ZIP code for your exact zone.
Utah hardiness zones by share of ZIP codes
What the zones mean for Utah gardeners
- Coldest and warmest towns: among towns with NOAA weather stations, Randolph (6,290 ft) is in zone 4a, while St George (2,857 ft) is in zone 8b. That is a difference of about 45°F in the coldest night of a typical winter.
- Same zone, different frost dates: within zone 6a, the median last spring frost ranges from April 30 at Logan Utah St University to June 21 at Brian Head, 52 days apart. Your zone tells you which perennials survive winter; your frost dates tell you when to plant.
Typical frost dates in each Utah zone
Medians across NOAA weather stations in each zone. Colder zones usually have later spring frosts, but local terrain can shift the dates by weeks.
| Zone | Last spring frost | First fall frost | Stations |
|---|---|---|---|
| 5b | May 22 | September 25 | 17 |
| 6a | May 21 | September 28 | 37 |
| 6b | May 5 | October 11 | 21 |
| 7a | April 27 | October 18 | 20 |
| 7b | April 10 | October 31 | 8 |
Hardiness zones for Utah cities
Zones at the National Weather Service stations, mostly city airports, with their median frost dates.
| Cedar City Municipal Airport | 6b | −5°F to 0°F | 5,586 | May 21 | Sep 29 |
| Delta | 6a | −10°F to −5°F | 4,620 | May 16 | Sep 29 |
| Hanksville | 7a | 0°F to 5°F | 4,308 | May 5 | Oct 3 |
| Logan Cache Airport | 6a | −10°F to −5°F | 4,454 | May 8 | Oct 2 |
| Ogden Hinkley Airport | 7a | 0°F to 5°F | 4,470 | Apr 22 | Oct 22 |
| Price Carbon County Airport | 6a | −10°F to −5°F | 5,921 | May 3 | Oct 12 |
| Salt Lake City Intl Airport | 7b | 5°F to 10°F | 4,225 | Apr 8 | Oct 31 |
| Vernal Municipal Airport | 5b | −15°F to −10°F | 5,260 | May 6 | Oct 7 |
Hardiness zones for 109 towns in Utah
Each NOAA weather station is shown with the USDA zone of the nearest ZIP code (within 8 miles). Coldest night is the zone's range for the average annual extreme minimum temperature. Click a column to sort.
| Alpine | 7a | 0°F to 5°F | 5,100 | May 3 | Oct 12 |
| Alta | 6a | −10°F to −5°F | 8,710 | Jun 11 | Sep 18 |
| Altamont | 5b | −15°F to −10°F | 6,456 | May 31 | Sep 23 |
| Alton | 6a | −10°F to −5°F | 7,098 | Jun 1 | Sep 30 |
| Angle | 5b | −15°F to −10°F | 6,410 | Jun 17 | Sep 12 |
| Bear Lake State Park | 5a | −20°F to −15°F | 5,928 | May 15 | Oct 4 |
| Beaver Canyon Pwr House | 6a | −10°F to −5°F | 7,275 | Jun 1 | Sep 28 |
| Blanding | 7a | 0°F to 5°F | 6,032 | Apr 28 | Oct 21 |
| Bluff | 7a | 0°F to 5°F | 4,319 | Apr 24 | Oct 13 |
| Boulder | 7a | 0°F to 5°F | 6,650 | May 4 | Oct 14 |
| Bountiful Bench | 6b | −5°F to 0°F | 4,950 | Apr 25 | Oct 24 |
| Bountiful-val Verda | 7b | 5°F to 10°F | 4,540 | Apr 24 | Oct 19 |
| Brian Head | 6a | −10°F to −5°F | 9,770 | Jun 21 | Sep 12 |
| Brigham City Waste Plt | 6b | −5°F to 0°F | 4,240 | May 5 | Oct 5 |
| Bryce Canyon National Park Hqrs | 6a | −10°F to −5°F | 7,890 | May 23 | Sep 27 |
| Castle Dale | 6a | −10°F to −5°F | 5,629 | May 18 | Sep 27 |
| Castle Valley 1SE | 7a | 0°F to 5°F | 4,905 | Apr 19 | Oct 21 |
| Cedar City Municipal Airport | 6b | −5°F to 0°F | 5,586 | May 21 | Sep 29 |
| Cedar Point | 6b | −5°F to 0°F | 6,760 | May 16 | Oct 11 |
| Circleville | 5b | −15°F to −10°F | 6,050 | May 23 | Sep 27 |
| City Creek Wtp | 6b | −5°F to 0°F | 5,340 | May 13 | Oct 7 |
| Coalville 13 E | 5b | −15°F to −10°F | 6,510 | Any month | Any month |
| Cottonwood Weir | 7b | 5°F to 10°F | 4,986 | Apr 29 | Oct 22 |
| Cutler Dam | 6a | −10°F to −5°F | 4,290 | May 3 | Oct 12 |
| Delta | 6a | −10°F to −5°F | 4,620 | May 16 | Sep 29 |
| Dewey | 6b | −5°F to 0°F | 4,120 | Apr 27 | Oct 9 |
| Dinosaur Nm-quarry Area | 5b | −15°F to −10°F | 4,802 | May 1 | Oct 6 |
| Draper-point Of Mountain | 7a | 0°F to 5°F | 4,506 | Apr 18 | Oct 22 |
| Echo Dam | 6a | −10°F to −5°F | 5,470 | May 30 | Sep 18 |
| Eden-liberty | 6a | −10°F to −5°F | 5,195 | May 25 | Sep 26 |
| Enterprise | 7a | 0°F to 5°F | 5,320 | May 21 | Oct 2 |
| Enterprise Beryl Junction | 5b | −15°F to −10°F | 5,150 | May 31 | Sep 20 |
| Ephraim | 6a | −10°F to −5°F | 5,498 | May 28 | Sep 20 |
| Escalante | 7a | 0°F to 5°F | 5,810 | May 8 | Oct 10 |
| Fairfield | 6a | −10°F to −5°F | 4,880 | Jun 2 | Sep 16 |
| Farmington 3 NW | 7b | 5°F to 10°F | 4,380 | Apr 19 | Oct 19 |
| Ferron | 6a | −10°F to −5°F | 5,923 | May 6 | Oct 10 |
| Fillmore | 6a | −10°F to −5°F | 5,127 | May 4 | Oct 14 |
| Fort Duchesne | 5b | −15°F to −10°F | 5,052 | May 19 | Oct 2 |
| Fremont Indian State Park | 6a | −10°F to −5°F | 5,920 | Jun 4 | Sep 21 |
| Garfield | 7b | 5°F to 10°F | 4,298 | Apr 3 | Nov 4 |
| Hanksville | 7a | 0°F to 5°F | 4,308 | May 5 | Oct 3 |
| Hatch | 6a | −10°F to −5°F | 6,893 | Jun 19 | Sep 13 |
| Huntsville Monastery | 6a | −10°F to −5°F | 5,140 | Jun 4 | Sep 16 |
| Ibapah | 6b | −5°F to 0°F | 5,279 | Jun 14 | Sep 8 |
| Jarvie Rch | 5b | −15°F to −10°F | 5,454 | May 19 | Sep 28 |
| Johnson Pass | 6b | −5°F to 0°F | 5,580 | May 15 | Oct 5 |
| Kanosh | 6b | −5°F to 0°F | 4,382 | Apr 30 | Oct 19 |
| Koosharem | 5b | −15°F to −10°F | 6,930 | Jun 6 | Sep 21 |
| La Verkin | 8a | 10°F to 15°F | 3,194 | Apr 1 | Nov 5 |
| Laketown | 5b | −15°F to −10°F | 5,980 | May 28 | Sep 24 |
| Levan | 6a | −10°F to −5°F | 5,298 | May 10 | Oct 7 |
| Loa | 6a | −10°F to −5°F | 7,070 | May 31 | Sep 21 |
| Logan 5 SW Experiment Farm | 6a | −10°F to −5°F | 4,488 | May 12 | Sep 28 |
| Logan Cache Airport | 6a | −10°F to −5°F | 4,454 | May 8 | Oct 2 |
| Logan Radio Kvnu | 6a | −10°F to −5°F | 4,475 | May 8 | Oct 2 |
| Logan Utah St University | 6a | −10°F to −5°F | 4,790 | Apr 30 | Oct 16 |
| Manila | 5b | −15°F to −10°F | 6,393 | May 22 | Sep 29 |
| Manti | 6a | −10°F to −5°F | 5,740 | May 11 | Oct 6 |
| Marysvale | 6a | −10°F to −5°F | 5,845 | May 24 | Sep 25 |
| Mexican Hat | 7b | 5°F to 10°F | 4,109 | Apr 11 | Oct 30 |
| Milford | 6a | −10°F to −5°F | 5,009 | May 10 | Oct 2 |
| Monticello 2E | 6b | −5°F to 0°F | 6,820 | May 19 | Oct 2 |
| Morgan | 6a | −10°F to −5°F | 5,100 | May 25 | Sep 24 |
| Moroni | 5b | −15°F to −10°F | 5,580 | May 26 | Sep 25 |
| Mountain Dell Dam | 6b | −5°F to 0°F | 5,420 | May 7 | Oct 14 |
| Myton | 5b | −15°F to −10°F | 5,085 | May 7 | Oct 5 |
| Neola | 6a | −10°F to −5°F | 5,950 | May 19 | Sep 29 |
| Nephi | 6a | −10°F to −5°F | 5,146 | May 6 | Oct 10 |
| New Harmony | 7a | 0°F to 5°F | 5,167 | May 9 | Oct 11 |
| Oak City | 6b | −5°F to 0°F | 5,095 | May 2 | Oct 13 |
| Ogden Hinkley Airport | 7a | 0°F to 5°F | 4,470 | Apr 22 | Oct 22 |
| Ogden NE Bench | 6b | −5°F to 0°F | 4,572 | Apr 19 | Oct 22 |
| Ogden Pioneer Ph | 6b | −5°F to 0°F | 4,350 | Apr 21 | Oct 23 |
| Ogden Sugar Factory | 7a | 0°F to 5°F | 4,280 | Apr 22 | Oct 18 |
| Orderville | 6b | −5°F to 0°F | 5,460 | May 15 | Oct 8 |
| Orem Trtmt Plt | 7a | 0°F to 5°F | 4,510 | Apr 19 | Oct 19 |
| Ouray 4NE | 5b | −15°F to −10°F | 4,674 | May 2 | Oct 3 |
| Park City | 6a | −10°F to −5°F | 6,900 | May 29 | Sep 25 |
| Pleasant Grove | 7a | 0°F to 5°F | 4,692 | Apr 17 | Oct 25 |
| Price Carbon County Airport | 6a | −10°F to −5°F | 5,921 | May 3 | Oct 12 |
| Provo Byu | 7a | 0°F to 5°F | 4,570 | Apr 18 | Oct 21 |
| Randolph | 4a | −30°F to −25°F | 6,290 | Jun 14 | Sep 1 |
| Richfield Radio Ksvc | 6a | −10°F to −5°F | 5,285 | May 21 | Sep 24 |
| Richmond | 6a | −10°F to −5°F | 4,680 | May 11 | Oct 5 |
| Rosette | 6a | −10°F to −5°F | 5,685 | May 21 | Oct 2 |
| Salt Lake City E Bench | 7a | 0°F to 5°F | 4,850 | Apr 25 | Oct 18 |
| Salt Lake City Intl Airport | 7b | 5°F to 10°F | 4,225 | Apr 8 | Oct 31 |
| Salt Lake Triad Center | 7b | 5°F to 10°F | 4,280 | Mar 31 | Nov 8 |
| Santaquin Chlorinator | 6b | −5°F to 0°F | 5,160 | May 4 | Oct 11 |
| Scipio | 5b | −15°F to −10°F | 5,314 | May 22 | Sep 25 |
| Snake Creek Powerhouse | 6a | −10°F to −5°F | 6,010 | May 31 | Sep 11 |
| Spanish Fk Pwr House | 7a | 0°F to 5°F | 4,720 | Apr 25 | Oct 18 |
| St George | 8b | 15°F to 20°F | 2,857 | Mar 14 | Nov 10 |
| Sundance | 6b | −5°F to 0°F | 6,620 | May 17 | Oct 5 |
| Sunnyside City | 6b | −5°F to 0°F | 6,511 | Apr 26 | Oct 25 |
| Thiokol Propulsion F S | 6a | −10°F to −5°F | 4,600 | May 17 | Sep 24 |
| Timpanogos Cave | 6a | −10°F to −5°F | 5,740 | May 2 | Oct 16 |
| Tooele | 7a | 0°F to 5°F | 4,944 | May 2 | Oct 16 |
| Tremonton | 6b | −5°F to 0°F | 4,310 | Apr 24 | Oct 17 |
| Trenton | 5b | −15°F to −10°F | 4,455 | May 17 | Sep 18 |
| Utah Lake Lehi | 7a | 0°F to 5°F | 4,505 | Apr 30 | Oct 9 |
| Vernal Municipal Airport | 5b | −15°F to −10°F | 5,260 | May 6 | Oct 7 |
| Vernon | 6b | −5°F to 0°F | 5,471 | Jun 1 | Sep 20 |
| Veyo Powerhouse | 7b | 5°F to 10°F | 4,600 | Apr 9 | Nov 5 |
| Wanship Dam | 5b | −15°F to −10°F | 5,940 | Jun 11 | Sep 12 |
| Weber Basin Pump Plt 3 | 7a | 0°F to 5°F | 4,900 | Apr 29 | Oct 20 |
| Woodruff | 5a | −20°F to −15°F | 6,315 | Any month | Any month |
| Zion National Park | 6b | −5°F to 0°F | 4,038 | Apr 13 | Nov 2 |
Frequently asked questions
What hardiness zone is Utah?
Utah is in USDA hardiness zones 4a–8b on the 2023 USDA Plant Hardiness Zone Map. Zone 6a is the most common, covering 32% of Utah's ZIP codes, and zone 7a covers 18%. Enter your ZIP code for your exact zone.
What does zone 6a mean?
Zone 6a means the average annual extreme minimum temperature, the coldest night of a typical winter, is −10°F to −5°F (−23°C to −21°C). Perennials, shrubs and trees rated for zone 6a or colder should survive winter there.
What is the coldest hardiness zone in Utah?
Zone 4a is the coldest zone mapped in Utah, found around Randolph, and zone 8b is the warmest, found around St George.
Did Utah's hardiness zones change in 2023?
The USDA released a new Plant Hardiness Zone Map in November 2023, based on 1991–2020 temperatures instead of 1976–2005. About half of the United States shifted half a zone warmer. Check your ZIP code here, because plant tags and older books may still list your 2012 zone.
When should I plant in zone 6a?
Hardiness zones don't set planting dates; frost dates do. Inside zone 6a in Utah, the median last spring frost varies from April 30 to June 21. Look up your local frost dates and plant tender crops such as tomatoes after the 10%-risk last-frost date.
Zone and frost dates: use both
Your hardiness zone answers one question: will this plant survive the winter here? Choose perennials, shrubs, trees and bulbs rated for your zone or a colder one. For vegetables and annuals, what matters is the length of the frost-free season. See Utah frost dates by town, or get a planting calendar for your ZIP code with start-indoors, transplant and sowing dates for 30 crops.
Sources and method
Zones are from the USDA 2023 Plant Hardiness Zone Map ZIP-code files published by the PRISM Climate Group, Oregon State University, based on 1991–2020 minimum temperatures. ZIP codes are assigned to states by USPS prefix. Town zones use the ZIP code nearest each NOAA 1991–2020 Climate Normals station. This is an independent tool, not an official USDA site. Full methodology.
Hardiness zones in other states
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
- Puerto Rico