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

Planting zone for 84108 — Salt Lake City, UT

ZIP code 84108 (Salt Lake City, Salt Lake County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 7 and the first fall frost October 14.

Where ZIP 84108 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostMay 7
First frostOct 14
2012 zone7a

Was 7a on the 2012 map — half a zone colder now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Salt Lake City, 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 Salt Lake City, UT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 7median — 50% chance of a later frost
Safe for tender plantsMay 27only 10% chance of frost after
First fall frostOctober 14median — 10% chance by Sep 29
Growing season158 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 21 and returns around October 26.

From the NOAA station Mtn Dell Dam, UT — 4 miles away, elevation 5,420 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 84108

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 26 – Apr 9
SpinachSow outdoors · Mar 26 – Apr 16
Broccoli, cabbageStart indoors · Feb 26 – Mar 12
Broccoli, cabbageTransplant · Apr 16 – Apr 30
Onion setsPlant outdoors · Apr 9 – Apr 23
PotatoesPlant outdoors · Apr 16 – Apr 30
LettuceSow outdoors · Apr 9 – Apr 23
Carrots, beetsSow outdoors · Apr 16 – Apr 30
TomatoesStart indoors · Mar 12 – Mar 26
TomatoesTransplant · May 14 – May 28
Peppers, eggplantStart indoors · Feb 26 – Mar 12
Peppers, eggplantTransplant · May 21 – Jun 4
BeansSow outdoors · May 14 – May 28
Sweet cornSow outdoors · May 14 – May 28
Cucumbers, squashSow outdoors · May 14 – May 28
Fall lettuce, spinachSow outdoors · Aug 19 – Sep 2
GarlicPlant cloves · Sep 30 – Nov 4
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 7) and first fall frost (Oct 14) 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 84108 came on Mar 23 — 21 days earlier than the 1991–2020 average (Apr 13).

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 6b in Utah

549 plants native to the lower 48 states, recorded in Utah, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 30

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 107

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 251

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 151

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 3

trumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °FVirginia 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 Salt Lake City, UT.

Soil in Salt Lake City, UT

The soil mapped at the center of ZIP 84108 is Brad — very cobbly loamy sand, somewhat excessively drained.

TextureVery cobbly loamy sanddrains and warms fast; dries out and needs more feeding
pH6.7neutral; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Brad very rocky loamy sand, 40 to 80 percent slopes.

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 84108; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Salt Lake City, UT

Summer high89 °Faverage high, July
Winter low20 °Faverage low, January
Hot days29days a year at 90 °F or more
Freezing nights158nights a year at 32 °F or less
Growing degree days2,678base 50 °F — the season’s usable heat
Longest day15 h 06 mindaylight on June 21
Shortest day9 h 14 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation38 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 40 °F, low 20 °F 40°20° JanFebruary: average high 44 °F, low 24 °F 44°24° FebMarch: average high 54 °F, low 30 °F 54°30° MarApril: average high 60 °F, low 36 °F 60°36° AprMay: average high 70 °F, low 43 °F 70°43° MayJune: average high 81 °F, low 49 °F 81°49° JunJuly: average high 89 °F, low 57 °F 89°57° JulAugust: average high 88 °F, low 56 °F 88°56° AugSeptember: average high 79 °F, low 48 °F 79°48° SepOctober: average high 65 °F, low 38 °F 65°38° OctNovember: average high 50 °F, low 30 °F 50°30° NovDecember: average high 40 °F, low 22 °F 40°22° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 4.59 in precipitation 4.6 JanFebruary: 3.83 in precipitation 3.8 FebMarch: 3.90 in precipitation 3.9 MarApril: 4.71 in precipitation 4.7 AprMay: 3.66 in precipitation 3.7 MayJune: 1.95 in precipitation 1.9 JunJuly: 0.83 in precipitation 0.8 JulAugust: 0.96 in precipitation 1.0 AugSeptember: 1.99 in precipitation 2.0 SepOctober: 3.19 in precipitation 3.2 OctNovember: 3.92 in precipitation 3.9 NovDecember: 4.47 in precipitation 4.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mtn Dell Dam, UT (4 mi away); precipitation: Louis Meadow, UT (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

841587a
Salt Lake City, UT · 3 mi
841036b
Salt Lake City, UT · 6 mi
841327a
Salt Lake City, UT · 6 mi
841137a
Salt Lake City, UT · 6 mi
841127a
Salt Lake City, UT · 7 mi
841487b
Salt Lake City, UT · 7 mi
840106b
Bountiful, UT · 7 mi
841096b
Salt Lake City, UT · 7 mi

All 47 ZIP codes in Salt Lake City → · Utah planting zones →

Questions about 84108

What planting zone is ZIP code 84108?

ZIP code 84108 (Salt Lake City, UT) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Salt Lake City, UT?

The median last spring frost (32 °F) near 84108 is May 7; after May 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mtn Dell Dam station.

When is the first frost in Salt Lake City, UT?

The median first fall frost near 84108 is October 14, giving a median frost-free growing season of 158 days.

When should I plant tomatoes in 84108?

Start tomato seeds indoors around Mar 12 – Mar 26 and set transplants outside around May 14 – May 28, one to three weeks after the median last frost.

How much rain and snow does 84108 get?

About 38 inches of precipitation a year (NOAA 1991–2020 normals, Louis Meadow station).

How hot do summers get in Salt Lake City, UT?

The average high peaks at 89 °F in July, with about 29 days a year at 90 °F or more.

What kind of soil does 84108 have?

The USDA soil survey maps Brad at the center of ZIP 84108: very cobbly loamy sand, somewhat excessively drained, pH about 6.7 (neutral).

Did spring come early in Salt Lake City, UT in 2026?

Spring leaf-out near 84108 came on Mar 23 in 2026, 21 days earlier than the 1991–2020 average (Apr 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Salt Lake City, UT?

Long-day onions: the longest day near 84108 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 84108 change?

Yes. The 2012 USDA map put 84108 in zone 7a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.