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

Planting zone for 82051 — Bosler, WY

ZIP code 82051 (Bosler, Albany County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 22 and the first fall frost September 24.

Where ZIP 82051 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.

Zone4a−30 to −25 °F

Coldest night−34.4 to −31.7 °C

Last frostMay 22

First frostSep 24

2012 zone4b

Was 4b 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 4a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Bosler, WY…

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 Bosler, WY

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 22median — 50% chance of a later frost

Safe for tender plantsJune 5only 10% chance of frost after

First fall frostSeptember 24median — 10% chance by Sep 9

Growing season125 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 7 and returns around October 4.

From the NOAA station Sybille Rsch Unit, WY — 18 miles away, elevation 6,086 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 82051

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 10 – Apr 24

SpinachSow outdoors · Apr 10 – May 1

Broccoli, cabbageStart indoors · Mar 13 – Mar 27

Broccoli, cabbageTransplant · May 1 – May 15

Onion setsPlant outdoors · Apr 24 – May 8

PotatoesPlant outdoors · May 1 – May 15

LettuceSow outdoors · Apr 24 – May 8

Carrots, beetsSow outdoors · May 1 – May 15

TomatoesStart indoors · Mar 27 – Apr 10

TomatoesTransplant · May 29 – Jun 12

Peppers, eggplantStart indoors · Mar 13 – Mar 27

Peppers, eggplantTransplant · Jun 5 – Jun 19

BeansSow outdoors · May 29 – Jun 12

Sweet cornSow outdoors · May 29 – Jun 12

Cucumbers, squashSow outdoors · May 29 – Jun 12

Fall lettuce, spinachSow outdoors · Jul 30 – Aug 13

GarlicPlant cloves · Sep 10 – Oct 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 22) and first fall frost (Sep 24) 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 82051 came on Mar 27 — 31 days earlier than the 1991–2020 average (Apr 27).

average
Apr 272026
Mar 27

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 4a in Wyoming

431 plants native to the lower 48 states, recorded in Wyoming, and rated by the USDA to survive −30 °F or colder — the bottom of zone 4a. 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 Bosler, WY.

Soil in Bosler, WY

The soil mapped at the center of ZIP 82051 is Forelle — loam, well drained.

TextureLoama good balance for most vegetables

pH7.6slightly alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.5%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classFarmland of statewide importance, if irrigatedUSDA classification

Map unit: Forelle loam, 0 to 6 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 82051; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Bosler, WY

Summer high83 °Faverage high, July

Winter low16 °Faverage low, January

Hot days11days a year at 90 °F or more

Freezing nights184nights a year at 32 °F or less

Growing degree days1,916base 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)

Precipitation15.2 inper year, rain and melted snow

Snowfall70 inper year; 50 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: Sybille Rsch Unit, WY (18 mi away); precipitation: Sybille Rsch Unit, WY (18 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

820724a

Laramie, WY · 13 mi

820834b

Rock River, WY · 20 mi

820615b

Horse Creek, WY · 27 mi

Wheatland, WY · 38 mi

Wyoming planting zones →

Questions about 82051

What planting zone is ZIP code 82051?

ZIP code 82051 (Bosler, WY) is in USDA hardiness zone 4a on the 2023 map: the coldest night of an average winter reaches −30 to −25 °F (−34.4 to −31.7 °C).

When is the last frost in Bosler, WY?

The median last spring frost (32 °F) near 82051 is May 22; after June 5 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Sybille Rsch Unit station.

When is the first frost in Bosler, WY?

The median first fall frost near 82051 is September 24, giving a median frost-free growing season of 125 days.

When should I plant tomatoes in 82051?

Start tomato seeds indoors around Mar 27 – Apr 10 and set transplants outside around May 29 – Jun 12, one to three weeks after the median last frost.

How much rain and snow does 82051 get?

About 15.2 inches of precipitation a year and 70 inches of snowfall (NOAA 1991–2020 normals, Sybille Rsch Unit station).

How hot do summers get in Bosler, WY?

The average high peaks at 83 °F in July, with about 11 days a year at 90 °F or more.

What kind of soil does 82051 have?

The USDA soil survey maps Forelle at the center of ZIP 82051: loam, well drained, pH about 7.6 (slightly alkaline).

Did spring come early in Bosler, WY in 2026?

Spring leaf-out near 82051 came on Mar 27 in 2026, 31 days earlier than the 1991–2020 average (Apr 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Bosler, WY?

Long-day onions: the longest day near 82051 is 15 h 12 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 82051 change?

Yes. The 2012 USDA map put 82051 in zone 4b; the 2023 map puts it in zone 4a. The newer map uses 1991–2020 data and more weather stations.