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

Planting zone for 81527 — Whitewater, CO

ZIP code 81527 (Whitewater, Mesa County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 23 and the first fall frost October 20.

Where ZIP 81527 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 frostApr 23
First frostOct 20
2012 zone6b

Was 6b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Whitewater, 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 Whitewater, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 23median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 5
Growing season179 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around November 1.

From the NOAA station Grand Junction 6ese, CO — 17 miles away, elevation 4,761 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 81527

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 12 – Mar 26
SpinachSow outdoors · Mar 12 – Apr 2
Broccoli, cabbageStart indoors · Feb 12 – Feb 26
Broccoli, cabbageTransplant · Apr 2 – Apr 16
Onion setsPlant outdoors · Mar 26 – Apr 9
PotatoesPlant outdoors · Apr 2 – Apr 16
LettuceSow outdoors · Mar 26 – Apr 9
Carrots, beetsSow outdoors · Apr 2 – Apr 16
TomatoesStart indoors · Feb 26 – Mar 12
TomatoesTransplant · Apr 30 – May 14
Peppers, eggplantStart indoors · Feb 12 – Feb 26
Peppers, eggplantTransplant · May 7 – May 21
BeansSow outdoors · Apr 30 – May 14
Sweet cornSow outdoors · Apr 30 – May 14
Cucumbers, squashSow outdoors · Apr 30 – May 14
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 23) and first fall frost (Oct 20) 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 81527 came on Mar 18 — 18 days earlier than the 1991–2020 average (Apr 5).

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 Whitewater, CO.

Soil in Whitewater, CO

The soil mapped at the center of ZIP 81527 is Sili — very cobbly clay loam, well drained.

TextureVery cobbly clay loamholds water and nutrients; slow to drain and warm up
pH7.6slightly alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Sili-Winnett-Badland complex, 3 to 25 percent slopes, extremely bouldery.

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 81527; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Whitewater, CO

Summer high93 °Faverage high, July
Winter low19 °Faverage low, January
Hot days67days a year at 90 °F or more
Freezing nights128nights a year at 32 °F or less
Growing degree days3,760base 50 °F — the season’s usable heat
Longest day14 h 53 mindaylight on June 21
Shortest day9 h 27 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation8.9 inper year, rain and melted snow
Snowfall13 inper year; 22 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 39 °F, low 19 °F 39°19° JanFebruary: average high 47 °F, low 25 °F 47°25° FebMarch: average high 58 °F, low 34 °F 58°34° MarApril: average high 65 °F, low 40 °F 65°40° AprMay: average high 76 °F, low 50 °F 76°50° MayJune: average high 88 °F, low 59 °F 88°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 54 °F 81°54° SepOctober: average high 67 °F, low 41 °F 67°41° OctNovember: average high 52 °F, low 30 °F 52°30° NovDecember: average high 40 °F, low 20 °F 40°20° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″January: 0.50 in precipitation, 3.4 in snowfall 0.5❄3 JanFebruary: 0.46 in precipitation, 2.1 in snowfall 0.5❄2 FebMarch: 0.77 in precipitation, 1.1 in snowfall 0.8❄1 MarApril: 0.96 in precipitation, 0.6 in snowfall 1.0❄1 AprMay: 0.93 in precipitation 0.9 MayJune: 0.45 in precipitation 0.5 JunJuly: 0.72 in precipitation 0.7 JulAugust: 0.78 in precipitation 0.8 AugSeptember: 1.21 in precipitation 1.2 SepOctober: 0.92 in precipitation, 0.2 in snowfall 0.9 OctNovember: 0.68 in precipitation, 1.7 in snowfall 0.7❄2 NovDecember: 0.51 in precipitation, 3.5 in snowfall 0.5❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Grand Junction 6ese, CO (17 mi away); precipitation: Grand Junction 6ese, CO (17 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

815027a
Grand Junction, CO · 15 mi
814166b
Delta, CO · 16 mi
815037a
Grand Junction, CO · 16 mi
815077a
Grand Junction, CO · 18 mi
815017a
Grand Junction, CO · 19 mi
815267a
Palisade, CO · 21 mi
815207a
Clifton, CO · 22 mi
815047a
Grand Junction, CO · 22 mi

Colorado planting zones →

Questions about 81527

What planting zone is ZIP code 81527?

ZIP code 81527 (Whitewater, 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 Whitewater, CO?

The median last spring frost (32 °F) near 81527 is April 23; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Grand Junction 6ese station.

When is the first frost in Whitewater, CO?

The median first fall frost near 81527 is October 20, giving a median frost-free growing season of 179 days.

When should I plant tomatoes in 81527?

Start tomato seeds indoors around Feb 26 – Mar 12 and set transplants outside around Apr 30 – May 14, one to three weeks after the median last frost.

How much rain and snow does 81527 get?

About 8.9 inches of precipitation a year and 13 inches of snowfall (NOAA 1991–2020 normals, Grand Junction 6ese station).

How hot do summers get in Whitewater, CO?

The average high peaks at 93 °F in July, with about 67 days a year at 90 °F or more.

What kind of soil does 81527 have?

The USDA soil survey maps Sili at the center of ZIP 81527: very cobbly clay loam, well drained, pH about 7.6 (slightly alkaline).

Did spring come early in Whitewater, CO in 2026?

Spring leaf-out near 81527 came on Mar 18 in 2026, 18 days earlier than the 1991–2020 average (Apr 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Whitewater, CO?

Intermediate onions: the longest day near 81527 is 14 h 53 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 81527 change?

Yes. The 2012 USDA map put 81527 in zone 6b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.