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

Planting zone for 80743 — Otis, CO

ZIP code 80743 (Otis, Washington County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is May 8 and the first fall frost October 6.

Where ZIP 80743 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.

Zone5b−15 to −10 °F
Coldest night−26.1 to −23.3 °C
Last frostMay 8
First frostOct 6
2012 zone5b

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 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Otis, 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 Otis, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 8median — 50% chance of a later frost
Safe for tender plantsMay 22only 10% chance of frost after
First fall frostOctober 6median — 10% chance by Sep 25
Growing season149 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 15.

From the NOAA station Akron 4 E, CO — 11 miles away, elevation 4,541 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 80743

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 27 – Apr 10
SpinachSow outdoors · Mar 27 – Apr 17
Broccoli, cabbageStart indoors · Feb 27 – Mar 13
Broccoli, cabbageTransplant · Apr 17 – May 1
Onion setsPlant outdoors · Apr 10 – Apr 24
PotatoesPlant outdoors · Apr 17 – May 1
LettuceSow outdoors · Apr 10 – Apr 24
Carrots, beetsSow outdoors · Apr 17 – May 1
TomatoesStart indoors · Mar 13 – Mar 27
TomatoesTransplant · May 15 – May 29
Peppers, eggplantStart indoors · Feb 27 – Mar 13
Peppers, eggplantTransplant · May 22 – Jun 5
BeansSow outdoors · May 15 – May 29
Sweet cornSow outdoors · May 15 – May 29
Cucumbers, squashSow outdoors · May 15 – May 29
Fall lettuce, spinachSow outdoors · Aug 11 – Aug 25
GarlicPlant cloves · Sep 22 – Oct 27
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 8) and first fall frost (Oct 6) 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 80743 came on Mar 1 — 25 days earlier than the 1991–2020 average (Mar 26).

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 5b in Colorado

546 plants native to the lower 48 states, recorded in Colorado, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. 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 98

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 246

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 163

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 Otis, CO.

Soil in Otis, CO

The soil mapped at the center of ZIP 80743 is Ascalon — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH7.0neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Ascalon sandy loam, 3 to 9 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 80743; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Otis, CO

Summer high89 °Faverage high, July
Winter low16 °Faverage low, January
Hot days48days a year at 90 °F or more
Freezing nights166nights a year at 32 °F or less
Growing degree days2,959base 50 °F — the season’s usable heat
Longest day15 h 02 mindaylight on June 21
Shortest day9 h 18 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation17.8 inper year, rain and melted snow
Snowfall28 inper year; 29 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 41 °F, low 16 °F 41°16° JanFebruary: average high 44 °F, low 18 °F 44°18° FebMarch: average high 54 °F, low 26 °F 54°26° MarApril: average high 61 °F, low 33 °F 61°33° AprMay: average high 71 °F, low 43 °F 71°43° MayJune: average high 83 °F, low 54 °F 83°54° JunJuly: average high 89 °F, low 60 °F 89°60° JulAugust: average high 87 °F, low 58 °F 87°58° AugSeptember: average high 79 °F, low 49 °F 79°49° SepOctober: average high 65 °F, low 36 °F 65°36° OctNovember: average high 52 °F, low 25 °F 52°25° NovDecember: average high 42 °F, low 16 °F 42°16° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.32 in precipitation, 3.9 in snowfall 0.3❄4 JanFebruary: 0.50 in precipitation, 5 in snowfall 0.5❄5 FebMarch: 0.78 in precipitation, 3.8 in snowfall 0.8❄4 MarApril: 1.54 in precipitation, 3.2 in snowfall 1.5❄3 AprMay: 2.93 in precipitation, 0.2 in snowfall 2.9 MayJune: 2.73 in precipitation 2.7 JunJuly: 3.17 in precipitation 3.2 JulAugust: 2.42 in precipitation 2.4 AugSeptember: 1.23 in precipitation, 0.3 in snowfall 1.2 SepOctober: 1.12 in precipitation, 2.4 in snowfall 1.1❄2 OctNovember: 0.58 in precipitation, 3.7 in snowfall 0.6❄4 NovDecember: 0.44 in precipitation, 5 in snowfall 0.4❄5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Akron 4 E, CO (11 mi away); precipitation: Yuma 10 Nw, CO (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

807205b
Akron, CO · 16 mi
807595b
Yuma, CO · 16 mi
807225b
Atwood, CO · 22 mi
807275b
Eckley, CO · 27 mi
807335b
Hillrose, CO · 29 mi
807285b
Fleming, CO · 30 mi
807315b
Haxtun, CO · 32 mi
807515b
Sterling, CO · 34 mi

Colorado planting zones →

Questions about 80743

What planting zone is ZIP code 80743?

ZIP code 80743 (Otis, CO) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Otis, CO?

The median last spring frost (32 °F) near 80743 is May 8; after May 22 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Akron 4 E station.

When is the first frost in Otis, CO?

The median first fall frost near 80743 is October 6, giving a median frost-free growing season of 149 days.

When should I plant tomatoes in 80743?

Start tomato seeds indoors around Mar 13 – Mar 27 and set transplants outside around May 15 – May 29, one to three weeks after the median last frost.

How much rain and snow does 80743 get?

About 17.8 inches of precipitation a year and 28 inches of snowfall (NOAA 1991–2020 normals, Yuma 10 Nw station).

How hot do summers get in Otis, CO?

The average high peaks at 89 °F in July, with about 48 days a year at 90 °F or more.

What kind of soil does 80743 have?

The USDA soil survey maps Ascalon at the center of ZIP 80743: sandy loam, well drained, pH about 7.0 (neutral).

Did spring come early in Otis, CO in 2026?

Spring leaf-out near 80743 came on Mar 1 in 2026, 25 days earlier than the 1991–2020 average (Mar 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Otis, CO?

Long-day onions: the longest day near 80743 is 15 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).