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

Planting zone for 80728 — Fleming, CO

ZIP code 80728 (Fleming, Logan County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is May 4 and the first fall frost October 11.

Where ZIP 80728 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 4
First frostOct 11
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 Fleming, 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 Fleming, CO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 4median — 50% chance of a later frost
Safe for tender plantsMay 16only 10% chance of frost after
First fall frostOctober 11median — 10% chance by Sep 29
Growing season157 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 25 and returns around October 19.

From the NOAA station Fleming 3sw, CO — within 1 mile, elevation 4,255 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 80728

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 23 – Apr 6
SpinachSow outdoors · Mar 23 – Apr 13
Broccoli, cabbageStart indoors · Feb 23 – Mar 9
Broccoli, cabbageTransplant · Apr 13 – Apr 27
Onion setsPlant outdoors · Apr 6 – Apr 20
PotatoesPlant outdoors · Apr 13 – Apr 27
LettuceSow outdoors · Apr 6 – Apr 20
Carrots, beetsSow outdoors · Apr 13 – Apr 27
TomatoesStart indoors · Mar 9 – Mar 23
TomatoesTransplant · May 11 – May 25
Peppers, eggplantStart indoors · Feb 23 – Mar 9
Peppers, eggplantTransplant · May 18 – Jun 1
BeansSow outdoors · May 11 – May 25
Sweet cornSow outdoors · May 11 – May 25
Cucumbers, squashSow outdoors · May 11 – May 25
Fall lettuce, spinachSow outdoors · Aug 16 – Aug 30
GarlicPlant cloves · Sep 27 – Nov 1
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 4) and first fall frost (Oct 11) 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 80728 came on Mar 2 — 24 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 Fleming, CO.

Soil in Fleming, CO

The soil mapped at the center of ZIP 80728 is Haxtun — 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 matter2.8%moderate
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Haxtun sandy loam, 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 80728; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Fleming, CO

Summer high90 °Faverage high, July
Winter low17 °Faverage low, January
Hot days53days a year at 90 °F or more
Freezing nights169nights a year at 32 °F or less
Growing degree days3,091base 50 °F — the season’s usable heat
Longest day15 h 05 mindaylight on June 21
Shortest day9 h 15 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation17.2 inper year, rain and melted snow
Snowfall37 inper year; 44 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 42 °F, low 17 °F 42°17° JanFebruary: average high 44 °F, low 19 °F 44°19° FebMarch: average high 54 °F, low 27 °F 54°27° MarApril: average high 62 °F, low 34 °F 62°34° AprMay: average high 71 °F, low 45 °F 71°45° MayJune: average high 83 °F, low 55 °F 83°55° JunJuly: average high 90 °F, low 61 °F 90°61° JulAugust: average high 88 °F, low 59 °F 88°59° AugSeptember: average high 80 °F, low 50 °F 80°50° SepOctober: average high 65 °F, low 36 °F 65°36° OctNovember: average high 52 °F, low 26 °F 52°26° NovDecember: average high 42 °F, low 17 °F 42°17° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.25 in precipitation, 3.7 in snowfall 0.3❄4 JanFebruary: 0.40 in precipitation, 7.4 in snowfall 0.4❄7 FebMarch: 0.90 in precipitation, 4.8 in snowfall 0.9❄5 MarApril: 1.81 in precipitation, 5.1 in snowfall 1.8❄5 AprMay: 3.09 in precipitation, 1.2 in snowfall 3.1❄1 MayJune: 2.49 in precipitation, 0.2 in snowfall 2.5 JunJuly: 2.60 in precipitation 2.6 JulAugust: 2.17 in precipitation 2.2 AugSeptember: 1.28 in precipitation, 0.2 in snowfall 1.3 SepOctober: 1.28 in precipitation, 3.1 in snowfall 1.3❄3 OctNovember: 0.51 in precipitation, 4.4 in snowfall 0.5❄4 NovDecember: 0.40 in precipitation, 6.9 in snowfall 0.4❄7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Fleming 3sw, CO (within 1 mile); precipitation: Fleming 3sw, CO (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

807365b
Iliff, CO · 14 mi
807315b
Haxtun, CO · 15 mi
807515b
Sterling, CO · 19 mi
807265b
Crook, CO · 20 mi
807225b
Atwood, CO · 21 mi
807465b
Paoli, CO · 22 mi
807495b
Sedgwick, CO · 23 mi
807475b
Peetz, CO · 26 mi

Colorado planting zones →

Questions about 80728

What planting zone is ZIP code 80728?

ZIP code 80728 (Fleming, 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 Fleming, CO?

The median last spring frost (32 °F) near 80728 is May 4; after May 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Fleming 3sw station.

When is the first frost in Fleming, CO?

The median first fall frost near 80728 is October 11, giving a median frost-free growing season of 157 days.

When should I plant tomatoes in 80728?

Start tomato seeds indoors around Mar 9 – Mar 23 and set transplants outside around May 11 – May 25, one to three weeks after the median last frost.

How much rain and snow does 80728 get?

About 17.2 inches of precipitation a year and 37 inches of snowfall (NOAA 1991–2020 normals, Fleming 3sw station).

How hot do summers get in Fleming, CO?

The average high peaks at 90 °F in July, with about 53 days a year at 90 °F or more.

What kind of soil does 80728 have?

The USDA soil survey maps Haxtun at the center of ZIP 80728: sandy loam, well drained, pH about 7.0 (neutral).

Did spring come early in Fleming, CO in 2026?

Spring leaf-out near 80728 came on Mar 2 in 2026, 24 days earlier than the 1991–2020 average (Mar 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Fleming, CO?

Long-day onions: the longest day near 80728 is 15 h 05 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).