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

Planting zone for 80459 — Kremmling, CO

ZIP code 80459 (Kremmling, Grand County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is June 14 and the first fall frost September 5.

Where ZIP 80459 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 14
First frostSep 5
2012 zone4a

Was 4a on the 2012 map — a full 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 Kremmling, 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 Kremmling, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 14median — 50% chance of a later frost
Safe for tender plantsJune 30only 10% chance of frost after
First fall frostSeptember 5median — 10% chance by Aug 26
Growing season80 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 28 and returns around September 16.

From the NOAA station Kremmling, CO — 7 miles away, elevation 7,461 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 80459

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · May 3 – May 17
SpinachSow outdoors · May 3 – May 24
Broccoli, cabbageStart indoors · Apr 5 – Apr 19
Broccoli, cabbageTransplant · May 24 – Jun 7
Onion setsPlant outdoors · May 17 – May 31
PotatoesPlant outdoors · May 24 – Jun 7
LettuceSow outdoors · May 17 – May 31
Carrots, beetsSow outdoors · May 24 – Jun 7
TomatoesStart indoors · Apr 19 – May 3
TomatoesTransplant · Jun 21 – Jul 5
Peppers, eggplantStart indoors · Apr 5 – Apr 19
Peppers, eggplantTransplant · Jun 28 – Jul 12
BeansSow outdoors · Jun 21 – Jul 5
Sweet cornSow outdoors · Jun 21 – Jul 5
Cucumbers, squashSow outdoors · Jun 21 – Jul 5
Fall lettuce, spinachSow outdoors · Jul 11 – Jul 25
GarlicPlant cloves · Aug 22 – Sep 26
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 14) and first fall frost (Sep 5) 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 80459 came on Apr 8 — 21 days earlier than the 1991–2020 average (Apr 29).

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 Kremmling, CO.

Soil in Kremmling, CO

The soil mapped at the center of ZIP 80459 is Harsha — loam, well drained.

TextureLoama good balance for most vegetables
pH7.2neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.25%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Harsha 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 80459; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Kremmling, CO

Summer high81 °Faverage high, July
Winter low−1 °Faverage low, January
Hot days2days a year at 90 °F or more
Freezing nights235nights a year at 32 °F or less
Growing degree days1,130base 50 °F — the season’s usable heat
Longest day15 h 02 mindaylight on June 21
Shortest day9 h 19 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation12 inper year, rain and melted snow
Snowfall52 inper year; 104 days with snow on the ground

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 26 °F, low -1 °F 26°−1° JanFebruary: average high 31 °F, low 3 °F 31°3° FebMarch: average high 43 °F, low 16 °F 43°16° MarApril: average high 53 °F, low 24 °F 53°24° AprMay: average high 64 °F, low 31 °F 64°31° MayJune: average high 76 °F, low 38 °F 76°38° JunJuly: average high 81 °F, low 44 °F 81°44° JulAugust: average high 79 °F, low 42 °F 79°42° AugSeptember: average high 72 °F, low 34 °F 72°34° SepOctober: average high 58 °F, low 23 °F 58°23° OctNovember: average high 42 °F, low 13 °F 42°13° NovDecember: average high 29 °F, low 1 °F 29°1° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″January: 0.73 in precipitation, 10.7 in snowfall 0.7❄11 JanFebruary: 0.72 in precipitation, 9.1 in snowfall 0.7❄9 FebMarch: 0.72 in precipitation, 6 in snowfall 0.7❄6 MarApril: 1.15 in precipitation, 5.8 in snowfall 1.1❄6 AprMay: 1.42 in precipitation, 1.9 in snowfall 1.4❄2 MayJune: 0.88 in precipitation 0.9 JunJuly: 1.40 in precipitation 1.4 JulAugust: 1.31 in precipitation 1.3 AugSeptember: 1.28 in precipitation, 0.1 in snowfall 1.3 SepOctober: 0.91 in precipitation, 3.1 in snowfall 0.9❄3 OctNovember: 0.74 in precipitation, 6.5 in snowfall 0.7❄7 NovDecember: 0.74 in precipitation, 9.2 in snowfall 0.7❄9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Kremmling, CO (7 mi away); precipitation: Kremmling, CO (7 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.

804515b
Hot Sulphur Springs, CO · 21 mi
804635b
Mc Coy, CO · 22 mi
804675a
Oak Creek, CO · 22 mi
804235b
Bond, CO · 23 mi
804685a
Parshall, CO · 23 mi
804734b
Rand, CO · 24 mi
804304b
Coalmont, CO · 25 mi
804465a
Granby, CO · 25 mi

Colorado planting zones →

Questions about 80459

What planting zone is ZIP code 80459?

ZIP code 80459 (Kremmling, 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 Kremmling, CO?

The median last spring frost (32 °F) near 80459 is June 14; after June 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Kremmling station.

When is the first frost in Kremmling, CO?

The median first fall frost near 80459 is September 5, giving a median frost-free growing season of 80 days.

When should I plant tomatoes in 80459?

Start tomato seeds indoors around Apr 19 – May 3 and set transplants outside around Jun 21 – Jul 5, one to three weeks after the median last frost.

How much rain and snow does 80459 get?

About 12 inches of precipitation a year and 52 inches of snowfall (NOAA 1991–2020 normals, Kremmling station).

How hot do summers get in Kremmling, CO?

The average high peaks at 81 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 80459 have?

The USDA soil survey maps Harsha at the center of ZIP 80459: loam, well drained, pH about 7.2 (neutral).

Did spring come early in Kremmling, CO in 2026?

Spring leaf-out near 80459 came on Apr 8 in 2026, 21 days earlier than the 1991–2020 average (Apr 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Kremmling, CO?

Long-day onions: the longest day near 80459 is 15 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 80459 change?

Yes. The 2012 USDA map put 80459 in zone 4a; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.