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

Planting zone for 81434 — Somerset, CO

ZIP code 81434 (Somerset, Gunnison County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 3 and the first fall frost October 12.

Where ZIP 81434 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 3
First frostOct 12
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 Somerset, 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 Somerset, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 3median — 50% chance of a later frost
Safe for tender plantsMay 18only 10% chance of frost after
First fall frostOctober 12median — 10% chance by Sep 27
Growing season159 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 23 and returns around October 21.

From the NOAA station Paonia 1sw, CO — 14 miles away, elevation 5,581 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 81434

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 22 – Apr 5
SpinachSow outdoors · Mar 22 – Apr 12
Broccoli, cabbageStart indoors · Feb 22 – Mar 8
Broccoli, cabbageTransplant · Apr 12 – Apr 26
Onion setsPlant outdoors · Apr 5 – Apr 19
PotatoesPlant outdoors · Apr 12 – Apr 26
LettuceSow outdoors · Apr 5 – Apr 19
Carrots, beetsSow outdoors · Apr 12 – Apr 26
TomatoesStart indoors · Mar 8 – Mar 22
TomatoesTransplant · May 10 – May 24
Peppers, eggplantStart indoors · Feb 22 – Mar 8
Peppers, eggplantTransplant · May 17 – May 31
BeansSow outdoors · May 10 – May 24
Sweet cornSow outdoors · May 10 – May 24
Cucumbers, squashSow outdoors · May 10 – May 24
Fall lettuce, spinachSow outdoors · Aug 17 – Aug 31
GarlicPlant cloves · Sep 28 – Nov 2
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 3) and first fall frost (Oct 12) 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 81434 came on Mar 31 — 24 days earlier than the 1991–2020 average (Apr 24).

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 Colorado

563 plants native to the lower 48 states, recorded in Colorado, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 28

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 104

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 251

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 167

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 4

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

Soil in Somerset, CO

The soil mapped at the center of ZIP 81434 is Hayrack — clay loam, well drained.

TextureClay loamholds water and nutrients; slow to drain and warm up
pH6.7neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Hayrack-Muggins-Nutras complex, 40 to 65 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 81434; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Somerset, CO

Summer high90 °Faverage high, July
Winter low16 °Faverage low, January
Hot days45days a year at 90 °F or more
Freezing nights148nights a year at 32 °F or less
Growing degree days2,863base 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
Precipitation16.9 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 39 °F, low 16 °F 39°16° JanFebruary: average high 45 °F, low 22 °F 45°22° FebMarch: average high 56 °F, low 29 °F 56°29° MarApril: average high 63 °F, low 34 °F 63°34° AprMay: average high 73 °F, low 43 °F 73°43° MayJune: average high 85 °F, low 51 °F 85°51° JunJuly: average high 90 °F, low 57 °F 90°57° JulAugust: average high 88 °F, low 56 °F 88°56° AugSeptember: average high 80 °F, low 48 °F 80°48° SepOctober: average high 67 °F, low 37 °F 67°37° OctNovember: average high 53 °F, low 27 °F 53°27° NovDecember: average high 40 °F, low 17 °F 40°17° Dec

Precipitation by month inches

0″1″2″January: 1.54 in precipitation 1.5 JanFebruary: 1.53 in precipitation 1.5 FebMarch: 1.29 in precipitation 1.3 MarApril: 1.56 in precipitation 1.6 AprMay: 1.50 in precipitation 1.5 MayJune: 0.61 in precipitation 0.6 JunJuly: 1.36 in precipitation 1.4 JulAugust: 1.44 in precipitation 1.4 AugSeptember: 1.83 in precipitation 1.8 SepOctober: 1.57 in precipitation 1.6 OctNovember: 0.97 in precipitation 1.0 NovDecember: 1.71 in precipitation 1.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Paonia 1sw, CO (14 mi away); precipitation: Paonia 2.1 Sse, CO (12 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

814286b
Paonia, CO · 9 mi
814196b
Hotchkiss, CO · 18 mi
816246a
Collbran, CO · 21 mi
812255a
Crested Butte, CO · 22 mi
816236a
Carbondale, CO · 23 mi
814206b
Lazear, CO · 23 mi
814135b
Cedaredge, CO · 25 mi
816546a
Snowmass, CO · 26 mi

Colorado planting zones →

Questions about 81434

What planting zone is ZIP code 81434?

ZIP code 81434 (Somerset, CO) 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 Somerset, CO?

The median last spring frost (32 °F) near 81434 is May 3; after May 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Paonia 1sw station.

When is the first frost in Somerset, CO?

The median first fall frost near 81434 is October 12, giving a median frost-free growing season of 159 days.

When should I plant tomatoes in 81434?

Start tomato seeds indoors around Mar 8 – Mar 22 and set transplants outside around May 10 – May 24, one to three weeks after the median last frost.

How much rain and snow does 81434 get?

About 16.9 inches of precipitation a year (NOAA 1991–2020 normals, Paonia 2.1 Sse station).

How hot do summers get in Somerset, CO?

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

What kind of soil does 81434 have?

The USDA soil survey maps Hayrack at the center of ZIP 81434: clay loam, well drained, pH about 6.7 (neutral).

Did spring come early in Somerset, CO in 2026?

Spring leaf-out near 81434 came on Mar 31 in 2026, 24 days earlier than the 1991–2020 average (Apr 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Somerset, CO?

Intermediate onions: the longest day near 81434 is 14 h 54 min, so day-neutral types bulb best; long-day varieties may not bulb fully.