Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 84728 — Garrison, UT

ZIP code 84728 (Garrison, Millard County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 12 and the first fall frost October 1.

Where ZIP 84728 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 frostMay 12

First frostOct 1

2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Garrison, 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 Garrison, UT

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 12median — 50% chance of a later frost

Safe for tender plantsJune 3only 10% chance of frost after

First fall frostOctober 1median — 10% chance by Sep 19

Growing season140 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 29 and returns around October 10.

From the NOAA station Eskdale, UT — 16 miles away, elevation 4,981 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 84728

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 31 – Apr 14

SpinachSow outdoors · Mar 31 – Apr 21

Broccoli, cabbageStart indoors · Mar 3 – Mar 17

Broccoli, cabbageTransplant · Apr 21 – May 5

Onion setsPlant outdoors · Apr 14 – Apr 28

PotatoesPlant outdoors · Apr 21 – May 5

LettuceSow outdoors · Apr 14 – Apr 28

Carrots, beetsSow outdoors · Apr 21 – May 5

TomatoesStart indoors · Mar 17 – Mar 31

TomatoesTransplant · May 19 – Jun 2

Peppers, eggplantStart indoors · Mar 3 – Mar 17

Peppers, eggplantTransplant · May 26 – Jun 9

BeansSow outdoors · May 19 – Jun 2

Sweet cornSow outdoors · May 19 – Jun 2

Cucumbers, squashSow outdoors · May 19 – Jun 2

Fall lettuce, spinachSow outdoors · Aug 6 – Aug 20

GarlicPlant cloves · Sep 17 – Oct 22

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 12) and first fall frost (Oct 1) 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 84728 came on Mar 5 — 17 days earlier than the 1991–2020 average (Mar 22).

average
Mar 222026
Mar 5

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.

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 Garrison, UT.

Soil in Garrison, UT

The soil mapped at the center of ZIP 84728 is Skumpah — silt loam, well drained.

TextureSilt loama good balance for most vegetables

pH8.6alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter0.75%low — add compost

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Skumpah family, 0 to 3 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 84728; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Garrison, UT

Summer high94 °Faverage high, July

Winter low16 °Faverage low, January

Hot days67days a year at 90 °F or more

Freezing nights157nights a year at 32 °F or less

Growing degree days3,133base 50 °F — the season’s usable heat

Longest day14 h 57 mindaylight on June 21

Shortest day9 h 24 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation6.4 inper year, rain and melted snow

Snowfall18 inper year; 17 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Eskdale, UT (16 mi away); precipitation: Eskdale, UT (16 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Utah planting zones →

Questions about 84728

What planting zone is ZIP code 84728?

ZIP code 84728 (Garrison, 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 Garrison, UT?

The median last spring frost (32 °F) near 84728 is May 12; after June 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Eskdale station.

When is the first frost in Garrison, UT?

The median first fall frost near 84728 is October 1, giving a median frost-free growing season of 140 days.

When should I plant tomatoes in 84728?

Start tomato seeds indoors around Mar 17 – Mar 31 and set transplants outside around May 19 – Jun 2, one to three weeks after the median last frost.

How much rain and snow does 84728 get?

About 6.4 inches of precipitation a year and 18 inches of snowfall (NOAA 1991–2020 normals, Eskdale station).

How hot do summers get in Garrison, UT?

The average high peaks at 94 °F in July, with about 67 days a year at 90 °F or more.

What kind of soil does 84728 have?

The USDA soil survey maps Skumpah at the center of ZIP 84728: silt loam, well drained, pH about 8.6 (alkaline).

Did spring come early in Garrison, UT in 2026?

Spring leaf-out near 84728 came on Mar 5 in 2026, 17 days earlier than the 1991–2020 average (Mar 22), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Garrison, UT?

Intermediate onions: the longest day near 84728 is 14 h 57 min, so day-neutral types bulb best; long-day varieties may not bulb fully.