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

Planting zone for 81225 — Crested Butte, CO

ZIP code 81225 (Crested Butte, Gunnison County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is June 2 and the first fall frost September 23.

Where ZIP 81225 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.

Zone5a−20 to −15 °F
Coldest night−28.9 to −26.1 °C
Last frostJun 2
First frostSep 23
2012 zone4b

Was 4b 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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Crested Butte, CO…

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 Crested Butte, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 2median — 50% chance of a later frost
Safe for tender plantsJune 17only 10% chance of frost after
First fall frostSeptember 23median — 10% chance by Sep 12
Growing season113 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 18 and returns around October 1.

From the NOAA station Aspen 1sw, CO — 18 miles away, elevation 8,176 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 81225

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 21 – May 5
SpinachSow outdoors · Apr 21 – May 12
Broccoli, cabbageStart indoors · Mar 24 – Apr 7
Broccoli, cabbageTransplant · May 12 – May 26
Onion setsPlant outdoors · May 5 – May 19
PotatoesPlant outdoors · May 12 – May 26
LettuceSow outdoors · May 5 – May 19
Carrots, beetsSow outdoors · May 12 – May 26
TomatoesStart indoors · Apr 7 – Apr 21
TomatoesTransplant · Jun 9 – Jun 23
Peppers, eggplantStart indoors · Mar 24 – Apr 7
Peppers, eggplantTransplant · Jun 16 – Jun 30
BeansSow outdoors · Jun 9 – Jun 23
Sweet cornSow outdoors · Jun 9 – Jun 23
Cucumbers, squashSow outdoors · Jun 9 – Jun 23
Fall lettuce, spinachSow outdoors · Jul 29 – Aug 12
GarlicPlant cloves · Sep 9 – Oct 14
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 2) and first fall frost (Sep 23) 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 81225 came on May 12 — 6 days earlier than the 1991–2020 average (May 18).

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 5a in Colorado

532 plants native to the lower 48 states, recorded in Colorado, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

Trees 27

American elm120 ft · blooms early spring · medium shade tolerance · to −46 °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 °Fblack willow100 ft · blooms early spring · high shade tolerance · to −58 °Fblue spruce100 ft · blooms late spring · medium shade tolerance · to −38 °F

Shrubs 95

alderleaf mountain mahogany15 ft · blooms late spring · medium shade tolerance · to −41 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FAmerican black currant3 ft · blooms early spring · to −46 °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 239

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine aster0.3 ft · blooms early summer · medium shade tolerance · to −28 °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 °F

Grasses 159

Alaska oniongrass3 ft · blooms mid spring · low shade tolerance · to −33 °Falkali 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 °F

Vines 3

riverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °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 Crested Butte, CO.

Soil in Crested Butte, CO

The center of ZIP 81225 is mapped as Rock outcrop: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

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 81225; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Crested Butte, CO

Summer high76 °Faverage high, July
Winter low−6 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights269nights a year at 32 °F or less
Growing degree days589base 50 °F — the season’s usable heat
Longest day14 h 54 mindaylight on June 21
Shortest day9 h 26 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation36.6 inper year, rain and melted snow
Snowfall389 inper year; 208 days with snow on the ground

Average high and low, by month

−20°−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 26 °F, low -6 °F 26°−6° JanFebruary: average high 29 °F, low -2 °F 29°−2° FebMarch: average high 38 °F, low 7 °F 38°7° MarApril: average high 47 °F, low 19 °F 47°19° AprMay: average high 58 °F, low 29 °F 58°29° MayJune: average high 70 °F, low 34 °F 70°34° JunJuly: average high 76 °F, low 40 °F 76°40° JulAugust: average high 74 °F, low 38 °F 74°38° AugSeptember: average high 66 °F, low 31 °F 66°31° SepOctober: average high 54 °F, low 22 °F 54°22° OctNovember: average high 39 °F, low 9 °F 39°9° NovDecember: average high 27 °F, low -4 °F 27°−4° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″January: 3.78 in precipitation, 61.1 in snowfall 3.8❄61 JanFebruary: 4.40 in precipitation, 62.6 in snowfall 4.4❄63 FebMarch: 4.11 in precipitation, 49.3 in snowfall 4.1❄49 MarApril: 3.57 in precipitation, 46.7 in snowfall 3.6❄47 AprMay: 2.71 in precipitation, 31.1 in snowfall 2.7❄31 MayJune: 1.24 in precipitation, 2.5 in snowfall 1.2❄3 JunJuly: 2.11 in precipitation 2.1 JulAugust: 2.80 in precipitation 2.8 AugSeptember: 2.84 in precipitation, 3.2 in snowfall 2.8❄3 SepOctober: 2.54 in precipitation, 25.7 in snowfall 2.5❄26 OctNovember: 2.95 in precipitation, 41.1 in snowfall 3.0❄41 NovDecember: 3.60 in precipitation, 65.7 in snowfall 3.6❄66 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Crested Butte, CO (6 mi away); precipitation: Crested Butte 6.2 N, CO (within 1 mile). 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.

812245a
Crested Butte, CO · 7 mi
816125a
Aspen, CO · 11 mi
816546a
Snowmass, CO · 17 mi
816155b
Snowmass Village, CO · 18 mi
812105a
Almont, CO · 21 mi
816236a
Carbondale, CO · 21 mi
814346a
Somerset, CO · 22 mi
816115a
Aspen, CO · 23 mi

All 2 ZIP codes in Crested Butte → · Colorado planting zones →

Questions about 81225

What planting zone is ZIP code 81225?

ZIP code 81225 (Crested Butte, CO) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Crested Butte, CO?

The median last spring frost (32 °F) near 81225 is June 2; after June 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Aspen 1sw station.

When is the first frost in Crested Butte, CO?

The median first fall frost near 81225 is September 23, giving a median frost-free growing season of 113 days.

When should I plant tomatoes in 81225?

Start tomato seeds indoors around Apr 7 – Apr 21 and set transplants outside around Jun 9 – Jun 23, one to three weeks after the median last frost.

How much rain and snow does 81225 get?

About 36.6 inches of precipitation a year and 389 inches of snowfall (NOAA 1991–2020 normals, Crested Butte 6.2 N station).

How hot do summers get in Crested Butte, CO?

The average high peaks at 76 °F in July, with about 0 days a year at 90 °F or more.

Did spring come early in Crested Butte, CO in 2026?

Spring leaf-out near 81225 came on May 12 in 2026, 6 days earlier than the 1991–2020 average (May 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Crested Butte, CO?

Intermediate onions: the longest day near 81225 is 14 h 54 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 81225 change?

Yes. The 2012 USDA map put 81225 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.