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

Planting zone for 84103 — Salt Lake City, UT

ZIP code 84103 (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 13 and the first fall frost October 7.

Where ZIP 84103 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 13
First frostOct 7
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 13median — 50% chance of a later frost
Safe for tender plantsMay 31only 10% chance of frost after
First fall frostOctober 7median — 10% chance by Sep 26
Growing season146 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 28 and returns around October 19.

From the NOAA station City Creek Wtp, UT — within 1 mile, elevation 5,341 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 84103

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 1 – Apr 15
SpinachSow outdoors · Apr 1 – Apr 22
Broccoli, cabbageStart indoors · Mar 4 – Mar 18
Broccoli, cabbageTransplant · Apr 22 – May 6
Onion setsPlant outdoors · Apr 15 – Apr 29
PotatoesPlant outdoors · Apr 22 – May 6
LettuceSow outdoors · Apr 15 – Apr 29
Carrots, beetsSow outdoors · Apr 22 – May 6
TomatoesStart indoors · Mar 18 – Apr 1
TomatoesTransplant · May 20 – Jun 3
Peppers, eggplantStart indoors · Mar 4 – Mar 18
Peppers, eggplantTransplant · May 27 – Jun 10
BeansSow outdoors · May 20 – Jun 3
Sweet cornSow outdoors · May 20 – Jun 3
Cucumbers, squashSow outdoors · May 20 – Jun 3
Fall lettuce, spinachSow outdoors · Aug 12 – Aug 26
GarlicPlant cloves · Sep 23 – Oct 28
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 13) and first fall frost (Oct 7) 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 84103 came on Mar 20 — 14 days earlier than the 1991–2020 average (Apr 3).

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 84103 is Harkers — cobbly loam, well drained.

TextureCobbly loama good balance for most vegetables
pH7.0neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter4%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Harkers soils, 6 to 40 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 84103; 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 days35days a year at 90 °F or more
Freezing nights157nights a year at 32 °F or less
Growing degree days2,543base 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)
Precipitation26.7 inper year, rain and melted snow
Snowfall114 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 38 °F, low 20 °F 38°20° JanFebruary: average high 43 °F, low 22 °F 43°22° FebMarch: average high 52 °F, low 29 °F 52°29° MarApril: average high 59 °F, low 34 °F 59°34° AprMay: average high 69 °F, low 41 °F 69°41° MayJune: average high 80 °F, low 49 °F 80°49° JunJuly: average high 89 °F, low 57 °F 89°57° JulAugust: average high 87 °F, low 56 °F 87°56° AugSeptember: average high 78 °F, low 47 °F 78°47° SepOctober: average high 63 °F, low 36 °F 63°36° OctNovember: average high 48 °F, low 27 °F 48°27° NovDecember: average high 38 °F, low 20 °F 38°20° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 2.77 in precipitation, 22.6 in snowfall 2.8❄23 JanFebruary: 2.47 in precipitation, 20.7 in snowfall 2.5❄21 FebMarch: 2.94 in precipitation, 16.2 in snowfall 2.9❄16 MarApril: 3.56 in precipitation, 13.2 in snowfall 3.6❄13 AprMay: 2.95 in precipitation, 0.8 in snowfall 3.0❄1 MayJune: 1.49 in precipitation 1.5 JunJuly: 0.68 in precipitation 0.7 JulAugust: 0.75 in precipitation 0.8 AugSeptember: 1.81 in precipitation 1.8 SepOctober: 2.28 in precipitation, 2.2 in snowfall 2.3❄2 OctNovember: 2.41 in precipitation, 11.6 in snowfall 2.4❄12 NovDecember: 2.62 in precipitation, 26.2 in snowfall 2.6❄26 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: City Creek Wtp, UT (within 1 mile); precipitation: City Creek Wtp, UT (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

841327a
Salt Lake City, UT · 2 mi
841127a
Salt Lake City, UT · 3 mi
841147b
Salt Lake City, UT · 3 mi
841137a
Salt Lake City, UT · 3 mi
841027b
Salt Lake City, UT · 3 mi
841337b
Salt Lake City, UT · 3 mi
841487b
Salt Lake City, UT · 3 mi
841807b
Salt Lake City, UT · 4 mi

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

Questions about 84103

What planting zone is ZIP code 84103?

ZIP code 84103 (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 84103 is May 13; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, City Creek Wtp station.

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

The median first fall frost near 84103 is October 7, giving a median frost-free growing season of 146 days.

When should I plant tomatoes in 84103?

Start tomato seeds indoors around Mar 18 – Apr 1 and set transplants outside around May 20 – Jun 3, one to three weeks after the median last frost.

How much rain and snow does 84103 get?

About 26.7 inches of precipitation a year and 114 inches of snowfall (NOAA 1991–2020 normals, City Creek Wtp station).

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

The average high peaks at 89 °F in July, with about 35 days a year at 90 °F or more.

What kind of soil does 84103 have?

The USDA soil survey maps Harkers at the center of ZIP 84103: cobbly loam, well drained, pH about 7.0 (neutral).

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

Spring leaf-out near 84103 came on Mar 20 in 2026, 14 days earlier than the 1991–2020 average (Apr 3), 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 84103 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 84103 change?

Yes. The 2012 USDA map put 84103 in zone 7a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.