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

Planting zone for 84744 — Koosharem, UT

ZIP code 84744 (Koosharem, Sevier County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is June 6 and the first fall frost September 21.

Where ZIP 84744 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostJun 6
First frostSep 21
2012 zone5b

Was 5b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Koosharem, 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 Koosharem, UT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 6median — 50% chance of a later frost
Safe for tender plantsJune 26only 10% chance of frost after
First fall frostSeptember 21median — 10% chance by Sep 5
Growing season104 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 26 and returns around September 29.

From the NOAA station Koosharem, UT — 8 miles away, elevation 6,929 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 84744

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 25 – May 9
SpinachSow outdoors · Apr 25 – May 16
Broccoli, cabbageStart indoors · Mar 28 – Apr 11
Broccoli, cabbageTransplant · May 16 – May 30
Onion setsPlant outdoors · May 9 – May 23
PotatoesPlant outdoors · May 16 – May 30
LettuceSow outdoors · May 9 – May 23
Carrots, beetsSow outdoors · May 16 – May 30
TomatoesStart indoors · Apr 11 – Apr 25
TomatoesTransplant · Jun 13 – Jun 27
Peppers, eggplantStart indoors · Mar 28 – Apr 11
Peppers, eggplantTransplant · Jun 20 – Jul 4
BeansSow outdoors · Jun 13 – Jun 27
Sweet cornSow outdoors · Jun 13 – Jun 27
Cucumbers, squashSow outdoors · Jun 13 – Jun 27
Fall lettuce, spinachSow outdoors · Jul 27 – Aug 10
GarlicPlant cloves · Sep 7 – Oct 12
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 6) and first fall frost (Sep 21) 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 84744 came on Mar 25 — 36 days earlier than the 1991–2020 average (Apr 30).

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 6a in Utah

546 plants native to the lower 48 states, recorded in Utah, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. 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 248

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 Koosharem, UT.

Soil in Koosharem, UT

The soil mapped at the center of ZIP 84744 is Keman family — very stony loam, well drained.

TextureVery stony loama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Keman family, 25 to 60 percent slopes, rubbly.

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 84744; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Koosharem, UT

Summer high85 °Faverage high, July
Winter low11 °Faverage low, December
Hot days8days a year at 90 °F or more
Freezing nights221nights a year at 32 °F or less
Growing degree days1,620base 50 °F — the season’s usable heat
Longest day14 h 52 mindaylight on June 21
Shortest day9 h 28 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation10.1 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 39 °F, low 12 °F 39°12° JanFebruary: average high 43 °F, low 16 °F 43°16° FebMarch: average high 52 °F, low 21 °F 52°21° MarApril: average high 59 °F, low 27 °F 59°27° AprMay: average high 69 °F, low 32 °F 69°32° MayJune: average high 80 °F, low 41 °F 80°41° JunJuly: average high 85 °F, low 48 °F 85°48° JulAugust: average high 82 °F, low 47 °F 82°47° AugSeptember: average high 75 °F, low 39 °F 75°39° SepOctober: average high 63 °F, low 28 °F 63°28° OctNovember: average high 51 °F, low 19 °F 51°19° NovDecember: average high 39 °F, low 11 °F 39°11° Dec

Precipitation by month inches

0″1″2″January: 0.70 in precipitation 0.7 JanFebruary: 0.48 in precipitation 0.5 FebMarch: 0.72 in precipitation 0.7 MarApril: 0.59 in precipitation 0.6 AprMay: 0.88 in precipitation 0.9 MayJune: 0.55 in precipitation 0.6 JunJuly: 1.29 in precipitation 1.3 JulAugust: 1.37 in precipitation 1.4 AugSeptember: 1.14 in precipitation 1.1 SepOctober: 1.16 in precipitation 1.2 OctNovember: 0.56 in precipitation 0.6 NovDecember: 0.65 in precipitation 0.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Koosharem, UT (8 mi away); precipitation: Koosharem, UT (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

847016a
Richfield, UT · 7 mi
847306a
Glenwood, UT · 9 mi
847116a
Annabella, UT · 10 mi
847546a
Monroe, UT · 11 mi
847325b
Greenwich, UT · 13 mi
847246a
Elsinore, UT · 13 mi
846576a
Sigurd, UT · 13 mi
847396a
Joseph, UT · 16 mi

Utah planting zones →

Questions about 84744

What planting zone is ZIP code 84744?

ZIP code 84744 (Koosharem, UT) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Koosharem, UT?

The median last spring frost (32 °F) near 84744 is June 6; after June 26 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Koosharem station.

When is the first frost in Koosharem, UT?

The median first fall frost near 84744 is September 21, giving a median frost-free growing season of 104 days.

When should I plant tomatoes in 84744?

Start tomato seeds indoors around Apr 11 – Apr 25 and set transplants outside around Jun 13 – Jun 27, one to three weeks after the median last frost.

How much rain and snow does 84744 get?

About 10.1 inches of precipitation a year (NOAA 1991–2020 normals, Koosharem station).

How hot do summers get in Koosharem, UT?

The average high peaks at 85 °F in July, with about 8 days a year at 90 °F or more.

What kind of soil does 84744 have?

The USDA soil survey maps Keman family at the center of ZIP 84744: very stony loam, well drained, pH about 6.5 (neutral).

Did spring come early in Koosharem, UT in 2026?

Spring leaf-out near 84744 came on Mar 25 in 2026, 36 days earlier than the 1991–2020 average (Apr 30), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Koosharem, UT?

Intermediate onions: the longest day near 84744 is 14 h 52 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 84744 change?

Yes. The 2012 USDA map put 84744 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.