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

Planting zone for 81520 — Clifton, CO

ZIP code 81520 (Clifton, Mesa County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 17 and the first fall frost October 26.

Where ZIP 81520 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.

Zone7a0 to 5 °F
Coldest night−17.8 to −15 °C
Last frostApr 17
First frostOct 26
2012 zone7a

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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Clifton, 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 Clifton, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 17median — 50% chance of a later frost
Safe for tender plantsMay 3only 10% chance of frost after
First fall frostOctober 26median — 10% chance by Oct 12
Growing season190 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 1 and returns around November 5.

From the NOAA station Palisade, CO — 4 miles away, elevation 4,751 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 81520

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 6 – Mar 20
SpinachSow outdoors · Mar 6 – Mar 27
Broccoli, cabbageStart indoors · Feb 6 – Feb 20
Broccoli, cabbageTransplant · Mar 27 – Apr 10
Onion setsPlant outdoors · Mar 20 – Apr 3
PotatoesPlant outdoors · Mar 27 – Apr 10
LettuceSow outdoors · Mar 20 – Apr 3
Carrots, beetsSow outdoors · Mar 27 – Apr 10
TomatoesStart indoors · Feb 20 – Mar 6
TomatoesTransplant · Apr 24 – May 8
Peppers, eggplantStart indoors · Feb 6 – Feb 20
Peppers, eggplantTransplant · May 1 – May 15
BeansSow outdoors · Apr 24 – May 8
Sweet cornSow outdoors · Apr 24 – May 8
Cucumbers, squashSow outdoors · Apr 24 – May 8
Fall lettuce, spinachSow outdoors · Aug 31 – Sep 14
GarlicPlant cloves · Oct 12 – Nov 16
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 17) and first fall frost (Oct 26) 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 81520 came on Mar 11 — 13 days earlier than the 1991–2020 average (Mar 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 7a in Colorado

573 plants native to the lower 48 states, recorded in Colorado, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. Each links to its USDA PLANTS profile.

Trees 28

Shrubs 107

Wildflowers & perennials 254

Grasses 171

Vines 4

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 Clifton, CO.

Soil in Clifton, CO

The soil mapped at the center of ZIP 81520 is Sagrlite — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH7.9alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Sagrlite-Turley-Fruitland complex, 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 81520; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Clifton, CO

Summer high93 °Faverage high, July
Winter low21 °Faverage low, January
Hot days60days a year at 90 °F or more
Freezing nights119nights a year at 32 °F or less
Growing degree days3,732base 50 °F — the season’s usable heat
Longest day14 h 55 mindaylight on June 21
Shortest day9 h 25 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation11.4 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 40 °F, low 21 °F 40°21° JanFebruary: average high 47 °F, low 26 °F 47°26° FebMarch: average high 58 °F, low 35 °F 58°35° MarApril: average high 66 °F, low 40 °F 66°40° AprMay: average high 76 °F, low 50 °F 76°50° MayJune: average high 87 °F, low 59 °F 87°59° JunJuly: average high 93 °F, low 65 °F 93°65° JulAugust: average high 90 °F, low 63 °F 90°63° AugSeptember: average high 81 °F, low 55 °F 81°55° SepOctober: average high 67 °F, low 42 °F 67°42° OctNovember: average high 53 °F, low 31 °F 53°31° NovDecember: average high 41 °F, low 22 °F 41°22° Dec

Precipitation by month inches

0″1″2″January: 0.83 in precipitation 0.8 JanFebruary: 0.82 in precipitation 0.8 FebMarch: 0.96 in precipitation 1.0 MarApril: 1.03 in precipitation 1.0 AprMay: 0.99 in precipitation 1.0 MayJune: 0.56 in precipitation 0.6 JunJuly: 0.84 in precipitation 0.8 JulAugust: 1.07 in precipitation 1.1 AugSeptember: 1.36 in precipitation 1.4 SepOctober: 1.59 in precipitation 1.6 OctNovember: 0.70 in precipitation 0.7 NovDecember: 0.70 in precipitation 0.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Palisade, CO (4 mi away); precipitation: Grand Junction 2.3 E, CO (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Colorado planting zones →

Questions about 81520

What planting zone is ZIP code 81520?

ZIP code 81520 (Clifton, CO) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Clifton, CO?

The median last spring frost (32 °F) near 81520 is April 17; after May 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Palisade station.

When is the first frost in Clifton, CO?

The median first fall frost near 81520 is October 26, giving a median frost-free growing season of 190 days.

When should I plant tomatoes in 81520?

Start tomato seeds indoors around Feb 20 – Mar 6 and set transplants outside around Apr 24 – May 8, one to three weeks after the median last frost.

How much rain and snow does 81520 get?

About 11.4 inches of precipitation a year (NOAA 1991–2020 normals, Grand Junction 2.3 E station).

How hot do summers get in Clifton, CO?

The average high peaks at 93 °F in July, with about 60 days a year at 90 °F or more.

What kind of soil does 81520 have?

The USDA soil survey maps Sagrlite at the center of ZIP 81520: silt loam, well drained, pH about 7.9 (alkaline).

Did spring come early in Clifton, CO in 2026?

Spring leaf-out near 81520 came on Mar 11 in 2026, 13 days earlier than the 1991–2020 average (Mar 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Clifton, CO?

Intermediate onions: the longest day near 81520 is 14 h 55 min, so day-neutral types bulb best; long-day varieties may not bulb fully.