Northern Utah: Davis, Weber, Cache, Box Elder, Morgan and Rich
Zones 4a to 7b; most cities fall in 6a and 6b.
Northern Utah holds the widest swing in the state. Ogden and Farmington sit at the warm end, with average last frosts of May 1 and May 5 and 176 and 158 frost-free days. Logan averages May 14 and 135 days, Morgan June 6 and 98 days, and Huntsville and Lake Town, up in the mountain valleys, have just 89 and 87 frost-free days.[1]
USU Extension says frost-free days across Cache Valley alone range from about 113 in Lewiston and Trenton to 158 on the USU campus.[1] That is also where the zone map is least reliable: the USDA map shows Cache County as mostly 5b, while local records for 1990 to 2019 point to 4b.[2]
Frost dates
| Town | Average last spring frost | Average first fall frost | Frost-free days |
|---|---|---|---|
| Farmington | May 5 | Oct. 10 | 158 |
| Huntsville | June 11 | Sept. 9 | 89 |
| Lake Town | June 15 | Sept. 10 | 87 |
| Logan | May 14 | Sept. 25 | 135 |
| Morgan | June 6 | Sept. 11 | 98 |
| Ogden | May 1 | Oct. 24 | 176 |
| Tremonton | May 3 | Oct. 10 | 160 |
When to plant vegetables
Hardy crops (A) go in first, then semi-hardy (B), tender (C) and very tender (D). (P) means protect with a cover.
| Location | Average last frost | Group A | Group B | Group C | Group D |
|---|---|---|---|---|---|
| Farmington | May 5 | March 15 | March 20 | May 5 | May 20 |
| Laketown | June 15 | May 1 | May 10 | June 1 | June 1 (P) |
| Logan, Southwest Farm | May 23 | April 15 | April 25 | May 23 | June 1 |
| Logan, USU campus | May 7 | April 1 | April 10 | May 7 | May 20 |
| Morgan | June 6 | March 15 | April 1 | May 20 | June 1 |
| Ogden | May 3 | March 15 | March 20 | May 3 | May 20 |
| Tremonton | May 3 | March 15 | March 20 | May 3 | May 20 |
See every crop group and all 36 locations
Which lawn calendar to use
Follow the northern Utah turf calendar, which lists Box Elder, Cache, Davis, Morgan, Rich and Weber counties.[3]
Good to know here
- Localscapes started in northern Utah, and in this part of the state a yard can have up to 35 percent lawn in front and 35 percent in back.[4]
- Weber Basin Water Conservancy District sponsors free Localscape classes.[5]
Zone by city
Zones come from the 2023 USDA map data matched to each city's nearest ZIP codes. A range means the ZIP codes around the city disagree; your own yard may differ, so check your address on the USDA map. Tap a city for its page.
- Ogden7a
- Layton7a–7b
- Logan6a
- Bountiful6b–7b
- Syracuse7a–7b
- Roy7a
- Clearfield7a–7b
- Kaysville7a–7b
- Fruit Heights7a–7b
- Farmington6b–7b
- North Ogden6b–7a
- Harrisville6b–7a
- North Salt Lake6b–7b
- Clinton7a
- Sunset7a
- West Haven7a
- South Ogden6b–7a
- Centerville6b–7b
- Riverdale6b–7a
- South Weber6b–7a
- Plain City6b–7a
- Farr West6b–7a
- Nibley6a
- Woods Cross7a–7b
- West Bountiful6b–7b
- West Point7a–7b
- Tremonton6b
- Smithfield6a
- North Logan6a
- Hyde Park6a
- Pleasant View6b–7a
- Hyrum6a
- Providence6a
- Hooper7a–7b
- Washington Terrace6b–7a
- Brigham City6a–6b
- Perry6a–7a
- Morgan6a
- Wellsville6a
- Richmond6a
- Garland6b
- Millville6a
- River Heights6a
- Willard6b–7a
- Marriott-Slaterville7a
- Lewiston5b–6a
- Honeyville6b
- Amalga6a
- Bear River City6b
- Clarkston6a
- Corinne6b
- Cornish5b–6a
- Deweyville6b
- Elwood6b
- Fielding6a–6b
- Garden City5a–6a
- Howell6a–6b
- Huntsville6a–7a
- Laketown4a–5b
- Mantua6a–6b
- Mendon6a–6b
- Newton5b–6a
- Ogden Valley7a
- Paradise6a
- Plymouth6a–6b
- Portage6a
- Randolph4a–5b
- Snowville6a
- Trenton5b–6a
- Uintah6b–7a
- Woodruff4a–5b
Other regions
- Salt Lake County and Tooele County
- Utah County
- Summit and Wasatch counties
- Central Utah: Juab, Millard, Sanpete, Sevier, Piute and Wayne
- Southern Utah: Washington, Iron, Kane, Garfield and Beaver
- Eastern Utah: Carbon, Emery, Grand, San Juan, Uintah, Duchesne and Daggett
Sources
- USU Extension, Average Frost Dates by Utah Location (Ask an Expert) ↗
- USU Extension Forestry, Hardiness Zones ↗
- USU Extension, Northern Utah Turfgrass Management Calendar ↗
- Plant Select, Localscapes: How Utah Is Building Buy-in for Waterwise Landscapes ↗
- KSL Brandview (Weber Basin Water Conservancy District), Design a landscape that works for Utah with Localscapes ↗