Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 84055 — Oakley, UT

ZIP code 84055 (Oakley, Summit County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is June 5 and the first fall frost September 17.

Where ZIP 84055 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone5b−15 to −10 °F
Coldest night−26.1 to −23.3 °C
Last frostJun 5
First frostSep 17
2012 zone5b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Oakley, UT…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Oakley, UT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 5median — 50% chance of a later frost
Safe for tender plantsJune 23only 10% chance of frost after
First fall frostSeptember 17median — 10% chance by Sep 1
Growing season100 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 19 and returns around September 27.

From the NOAA station Kamas, UT — 10 miles away, elevation 6,480 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 84055

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 24 – May 8
SpinachSow outdoors · Apr 24 – May 15
Broccoli, cabbageStart indoors · Mar 27 – Apr 10
Broccoli, cabbageTransplant · May 15 – May 29
Onion setsPlant outdoors · May 8 – May 22
PotatoesPlant outdoors · May 15 – May 29
LettuceSow outdoors · May 8 – May 22
Carrots, beetsSow outdoors · May 15 – May 29
TomatoesStart indoors · Apr 10 – Apr 24
TomatoesTransplant · Jun 12 – Jun 26
Peppers, eggplantStart indoors · Mar 27 – Apr 10
Peppers, eggplantTransplant · Jun 19 – Jul 3
BeansSow outdoors · Jun 12 – Jun 26
Sweet cornSow outdoors · Jun 12 – Jun 26
Cucumbers, squashSow outdoors · Jun 12 – Jun 26
Fall lettuce, spinachSow outdoors · Jul 23 – Aug 6
GarlicPlant cloves · Sep 3 – Oct 8
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 5) and first fall frost (Sep 17) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 84055 came on Apr 11 — 25 days earlier than the 1991–2020 average (May 6).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 5b in Utah

517 plants native to the lower 48 states, recorded in Utah, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

Trees 28

American beech80 ft · blooms mid spring · low shade tolerance · to −44 °FArizona cypress50 ft · blooms spring · low shade tolerance · to −23 °FArizona walnut50 ft · blooms late spring · high shade tolerance · to −33 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fblack walnut100 ft · blooms late spring · high shade tolerance · to −28 °F

Shrubs 94

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °Falderleaf mountain mahogany15 ft · blooms late spring · medium shade tolerance · to −41 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °FApache plume6 ft · blooms late spring · high shade tolerance · to −23 °F

Wildflowers & perennials 238

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bistort1.5 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °F

Grasses 148

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °FAlpine Meadow-Foxtail0.5 ft · blooms mid spring · medium shade tolerance · to −33 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °Fanalogue sedge1.5 ft · blooms late spring · medium shade tolerance · to −38 °Farctic bluegrass2 ft · high shade tolerance · to −62 °F

Vines 2

Virginia creeper1 ft · blooms late spring · medium shade tolerance · to −28 °Fwestern white clematis1 ft · blooms mid summer · medium shade tolerance · to −38 °F

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Oakley, UT.

Soil in Oakley, UT

The center of ZIP 84055 is mapped as Rubble land, talus: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 84055; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Oakley, UT

Summer high85 °Faverage high, July
Winter low15 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights196nights a year at 32 °F or less
Growing degree days1,709base 50 °F — the season’s usable heat
Longest day15 h 06 mindaylight on June 21
Shortest day9 h 15 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation27.5 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 35 °F, low 15 °F 35°15° JanFebruary: average high 38 °F, low 17 °F 38°17° FebMarch: average high 47 °F, low 25 °F 47°25° MarApril: average high 55 °F, low 30 °F 55°30° AprMay: average high 65 °F, low 36 °F 65°36° MayJune: average high 76 °F, low 43 °F 76°43° JunJuly: average high 85 °F, low 50 °F 85°50° JulAugust: average high 83 °F, low 49 °F 83°49° AugSeptember: average high 74 °F, low 41 °F 74°41° SepOctober: average high 59 °F, low 31 °F 59°31° OctNovember: average high 45 °F, low 23 °F 45°23° NovDecember: average high 34 °F, low 16 °F 34°16° Dec

Precipitation by month inches

0″1″2″3″4″January: 3.06 in precipitation 3.1 JanFebruary: 2.62 in precipitation 2.6 FebMarch: 2.69 in precipitation 2.7 MarApril: 3.10 in precipitation 3.1 AprMay: 2.70 in precipitation 2.7 MayJune: 1.43 in precipitation 1.4 JunJuly: 1.17 in precipitation 1.2 JulAugust: 1.54 in precipitation 1.5 AugSeptember: 1.93 in precipitation 1.9 SepOctober: 2.12 in precipitation 2.1 OctNovember: 2.45 in precipitation 2.5 NovDecember: 2.69 in precipitation 2.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Kamas, UT (10 mi away); precipitation: Smith & Morehouse, UT (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

3 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

840365b
Kamas, UT · 7 mi
840615b
Peoa, UT · 9 mi
840175b
Coalville, UT · 15 mi
840685b
Park City, UT · 19 mi
840606a
Park City, UT · 20 mi
840985b
Park City, UT · 20 mi
840246a
Echo, UT · 24 mi
840336a
Henefer, UT · 24 mi

Utah planting zones →

Questions about 84055

What planting zone is ZIP code 84055?

ZIP code 84055 (Oakley, UT) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Oakley, UT?

The median last spring frost (32 °F) near 84055 is June 5; after June 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Kamas station.

When is the first frost in Oakley, UT?

The median first fall frost near 84055 is September 17, giving a median frost-free growing season of 100 days.

When should I plant tomatoes in 84055?

Start tomato seeds indoors around Apr 10 – Apr 24 and set transplants outside around Jun 12 – Jun 26, one to three weeks after the median last frost.

How much rain and snow does 84055 get?

About 27.5 inches of precipitation a year (NOAA 1991–2020 normals, Smith & Morehouse station).

How hot do summers get in Oakley, UT?

The average high peaks at 85 °F in July, with about 17 days a year at 90 °F or more.

Did spring come early in Oakley, UT in 2026?

Spring leaf-out near 84055 came on Apr 11 in 2026, 25 days earlier than the 1991–2020 average (May 6), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Oakley, UT?

Long-day onions: the longest day near 84055 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).