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

Planting zone for 84721 — Cedar City, UT

ZIP code 84721 (Cedar City, Iron County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 21 and the first fall frost September 29.

Where ZIP 84721 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 21
First frostSep 29
2012 zone6b

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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Cedar 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 Cedar City, UT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 21median — 50% chance of a later frost
Safe for tender plantsJune 8only 10% chance of frost after
First fall frostSeptember 29median — 10% chance by Sep 17
Growing season130 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 6 and returns around October 9.

From the NOAA station Cedar City Municipal Airport, UT — 5 miles away, elevation 5,588 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 84721

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 9 – Apr 23
SpinachSow outdoors · Apr 9 – Apr 30
Broccoli, cabbageStart indoors · Mar 12 – Mar 26
Broccoli, cabbageTransplant · Apr 30 – May 14
Onion setsPlant outdoors · Apr 23 – May 7
PotatoesPlant outdoors · Apr 30 – May 14
LettuceSow outdoors · Apr 23 – May 7
Carrots, beetsSow outdoors · Apr 30 – May 14
TomatoesStart indoors · Mar 26 – Apr 9
TomatoesTransplant · May 28 – Jun 11
Peppers, eggplantStart indoors · Mar 12 – Mar 26
Peppers, eggplantTransplant · Jun 4 – Jun 18
BeansSow outdoors · May 28 – Jun 11
Sweet cornSow outdoors · May 28 – Jun 11
Cucumbers, squashSow outdoors · May 28 – Jun 11
Fall lettuce, spinachSow outdoors · Aug 4 – Aug 18
GarlicPlant cloves · Sep 15 – Oct 20
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 21) and first fall frost (Sep 29) 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 84721 came on Mar 7 — 18 days earlier than the 1991–2020 average (Mar 25).

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 Cedar City, UT.

Soil in Cedar City, UT

The soil mapped at the center of ZIP 84721 is Woodrow — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH8.2alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Woodrow silty clay loam, 0 to 2 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 84721; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cedar City, UT

Summer high91 °Faverage high, July
Winter low16 °Faverage low, December
Hot days44days a year at 90 °F or more
Freezing nights169nights a year at 32 °F or less
Growing degree days2,730base 50 °F — the season’s usable heat
Longest day14 h 47 mindaylight on June 21
Shortest day9 h 33 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation11 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 43 °F, low 18 °F 43°18° JanFebruary: average high 47 °F, low 21 °F 47°21° FebMarch: average high 56 °F, low 27 °F 56°27° MarApril: average high 63 °F, low 32 °F 63°32° AprMay: average high 73 °F, low 40 °F 73°40° MayJune: average high 85 °F, low 49 °F 85°49° JunJuly: average high 91 °F, low 57 °F 91°57° JulAugust: average high 89 °F, low 56 °F 89°56° AugSeptember: average high 81 °F, low 46 °F 81°46° SepOctober: average high 67 °F, low 34 °F 67°34° OctNovember: average high 53 °F, low 24 °F 53°24° NovDecember: average high 42 °F, low 16 °F 42°16° Dec

Precipitation by month inches

0″1″2″January: 0.82 in precipitation 0.8 JanFebruary: 0.98 in precipitation 1.0 FebMarch: 1.23 in precipitation 1.2 MarApril: 1.01 in precipitation 1.0 AprMay: 0.94 in precipitation 0.9 MayJune: 0.48 in precipitation 0.5 JunJuly: 1.02 in precipitation 1.0 JulAugust: 0.86 in precipitation 0.9 AugSeptember: 0.75 in precipitation 0.8 SepOctober: 1.23 in precipitation 1.2 OctNovember: 0.84 in precipitation 0.8 NovDecember: 0.88 in precipitation 0.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cedar City Municipal Airport, UT (5 mi away); precipitation: Cedar City Municipal Airport, UT (5 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.

847726b
Summit, UT · 10 mi
847206b
Cedar City, UT · 15 mi
847616a
Parowan, UT · 16 mi
847426b
Kanarraville, UT · 17 mi
847196a
Brian Head, UT · 21 mi
847577a
New Harmony, UT · 22 mi
847565b
Newcastle, UT · 23 mi
847606a
Paragonah, UT · 29 mi

All 2 ZIP codes in Cedar City → · Utah planting zones →

Questions about 84721

What planting zone is ZIP code 84721?

ZIP code 84721 (Cedar 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 Cedar City, UT?

The median last spring frost (32 °F) near 84721 is May 21; after June 8 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cedar City Municipal Airport station.

When is the first frost in Cedar City, UT?

The median first fall frost near 84721 is September 29, giving a median frost-free growing season of 130 days.

When should I plant tomatoes in 84721?

Start tomato seeds indoors around Mar 26 – Apr 9 and set transplants outside around May 28 – Jun 11, one to three weeks after the median last frost.

How much rain and snow does 84721 get?

About 11 inches of precipitation a year (NOAA 1991–2020 normals, Cedar City Municipal Airport station).

How hot do summers get in Cedar City, UT?

The average high peaks at 91 °F in July, with about 44 days a year at 90 °F or more.

What kind of soil does 84721 have?

The USDA soil survey maps Woodrow at the center of ZIP 84721: silty clay loam, well drained, pH about 8.2 (alkaline).

Did spring come early in Cedar City, UT in 2026?

Spring leaf-out near 84721 came on Mar 7 in 2026, 18 days earlier than the 1991–2020 average (Mar 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cedar City, UT?

Intermediate onions: the longest day near 84721 is 14 h 47 min, so day-neutral types bulb best; long-day varieties may not bulb fully.