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

Planting zone for 84337 — Tremonton, UT

ZIP code 84337 (Tremonton, Box Elder County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 24 and the first fall frost October 17.

Where ZIP 84337 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 frostApr 24
First frostOct 17
2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Tremonton, 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 Tremonton, UT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 24median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 17median — 10% chance by Oct 3
Growing season175 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 9 and returns around October 26.

From the NOAA station Tremonton, UT — 6 miles away, elevation 4,311 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 84337

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 13 – Mar 27
SpinachSow outdoors · Mar 13 – Apr 3
Broccoli, cabbageStart indoors · Feb 13 – Feb 27
Broccoli, cabbageTransplant · Apr 3 – Apr 17
Onion setsPlant outdoors · Mar 27 – Apr 10
PotatoesPlant outdoors · Apr 3 – Apr 17
LettuceSow outdoors · Mar 27 – Apr 10
Carrots, beetsSow outdoors · Apr 3 – Apr 17
TomatoesStart indoors · Feb 27 – Mar 13
TomatoesTransplant · May 1 – May 15
Peppers, eggplantStart indoors · Feb 13 – Feb 27
Peppers, eggplantTransplant · May 8 – May 22
BeansSow outdoors · May 1 – May 15
Sweet cornSow outdoors · May 1 – May 15
Cucumbers, squashSow outdoors · May 1 – May 15
Fall lettuce, spinachSow outdoors · Aug 22 – Sep 5
GarlicPlant cloves · Oct 3 – Nov 7
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 24) and first fall frost (Oct 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 84337 came on Mar 15 — 18 days earlier than the 1991–2020 average (Apr 2).

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).

Soil in Tremonton, UT

The soil mapped at the center of ZIP 84337 is Collett — silty clay loam, somewhat poorly drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH7.6slightly alkaline; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2.6%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Collett 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 84337; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Tremonton, UT

Summer high91 °Faverage high, July
Winter low19 °Faverage low, January
Hot days45days a year at 90 °F or more
Freezing nights132nights a year at 32 °F or less
Growing degree days3,035base 50 °F — the season’s usable heat
Longest day15 h 12 mindaylight on June 21
Shortest day9 h 09 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation15.8 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 36 °F, low 19 °F 36°19° JanFebruary: average high 41 °F, low 23 °F 41°23° FebMarch: average high 53 °F, low 32 °F 53°32° MarApril: average high 61 °F, low 37 °F 61°37° AprMay: average high 70 °F, low 46 °F 70°46° MayJune: average high 81 °F, low 53 °F 81°53° JunJuly: average high 91 °F, low 62 °F 91°62° JulAugust: average high 90 °F, low 60 °F 90°60° AugSeptember: average high 79 °F, low 50 °F 79°50° SepOctober: average high 65 °F, low 38 °F 65°38° OctNovember: average high 49 °F, low 28 °F 49°28° NovDecember: average high 37 °F, low 21 °F 37°21° Dec

Precipitation by month inches

0″1″2″3″January: 1.64 in precipitation 1.6 JanFebruary: 1.27 in precipitation 1.3 FebMarch: 1.58 in precipitation 1.6 MarApril: 1.68 in precipitation 1.7 AprMay: 2.16 in precipitation 2.2 MayJune: 1.13 in precipitation 1.1 JunJuly: 0.57 in precipitation 0.6 JulAugust: 0.67 in precipitation 0.7 AugSeptember: 1.26 in precipitation 1.3 SepOctober: 1.63 in precipitation 1.6 OctNovember: 0.83 in precipitation 0.8 NovDecember: 1.40 in precipitation 1.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Tremonton, UT (6 mi away); precipitation: Thatcher 1.7 Ese, UT (within 1 mile). 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.

843126b
Garland, UT · 9 mi
843346b
Riverside, UT · 10 mi
843096b
Deweyville, UT · 10 mi
843016b
Bear River City, UT · 10 mi
843146b
Honeyville, UT · 10 mi
843166a
Howell, UT · 10 mi
843116a
Fielding, UT · 13 mi
843066a
Collinston, UT · 13 mi

Utah planting zones →

Questions about 84337

What planting zone is ZIP code 84337?

ZIP code 84337 (Tremonton, 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 Tremonton, UT?

The median last spring frost (32 °F) near 84337 is April 24; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Tremonton station.

When is the first frost in Tremonton, UT?

The median first fall frost near 84337 is October 17, giving a median frost-free growing season of 175 days.

When should I plant tomatoes in 84337?

Start tomato seeds indoors around Feb 27 – Mar 13 and set transplants outside around May 1 – May 15, one to three weeks after the median last frost.

How much rain and snow does 84337 get?

About 15.8 inches of precipitation a year (NOAA 1991–2020 normals, Thatcher 1.7 Ese station).

How hot do summers get in Tremonton, UT?

The average high peaks at 91 °F in July, with about 45 days a year at 90 °F or more.

What kind of soil does 84337 have?

The USDA soil survey maps Collett at the center of ZIP 84337: silty clay loam, somewhat poorly drained, pH about 7.6 (slightly alkaline).

Did spring come early in Tremonton, UT in 2026?

Spring leaf-out near 84337 came on Mar 15 in 2026, 18 days earlier than the 1991–2020 average (Apr 2), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Tremonton, UT?

Long-day onions: the longest day near 84337 is 15 h 12 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 84337 change?

Yes. The 2012 USDA map put 84337 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.