Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 81646 — Molina, CO

ZIP code 81646 (Molina, Mesa County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is May 17 and the first fall frost September 30.

Where ZIP 81646 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 17

First frostSep 30

2012 zone6b

Was 6b on the 2012 map — a full zone colder now. 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 Molina, 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 Molina, CO

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 17median — 50% chance of a later frost

Safe for tender plantsJune 3only 10% chance of frost after

First fall frostSeptember 30median — 10% chance by Sep 18

Growing season136 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 3 and returns around October 9.

From the NOAA station Collbran 1wsw, CO — 9 miles away, elevation 6,011 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 81646

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 5 – Apr 19

SpinachSow outdoors · Apr 5 – Apr 26

Broccoli, cabbageStart indoors · Mar 8 – Mar 22

Broccoli, cabbageTransplant · Apr 26 – May 10

Onion setsPlant outdoors · Apr 19 – May 3

PotatoesPlant outdoors · Apr 26 – May 10

LettuceSow outdoors · Apr 19 – May 3

Carrots, beetsSow outdoors · Apr 26 – May 10

TomatoesStart indoors · Mar 22 – Apr 5

TomatoesTransplant · May 24 – Jun 7

Peppers, eggplantStart indoors · Mar 8 – Mar 22

Peppers, eggplantTransplant · May 31 – Jun 14

BeansSow outdoors · May 24 – Jun 7

Sweet cornSow outdoors · May 24 – Jun 7

Cucumbers, squashSow outdoors · May 24 – Jun 7

Fall lettuce, spinachSow outdoors · Aug 5 – Aug 19

GarlicPlant cloves · Sep 16 – Oct 21

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 17) and first fall frost (Sep 30) 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 81646 came on May 7 — 11 days later than the 1991–2020 average (Apr 26).

average
Apr 262026
May 7

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.

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 Molina, CO.

Soil in Molina, CO

The soil mapped at the center of ZIP 81646 is Needleton family — cobbly loam, well drained.

TextureCobbly loama good balance for most vegetables

pH6.1slightly acidic; 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: Needleton-Scout families complex, 5 to 40 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 81646; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Molina, CO

Summer high68 °Faverage high, July

Winter low4 °Faverage low, February

Hot days0days a year at 90 °F or more

Freezing nights256nights a year at 32 °F or less

Growing degree days345base 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

Precipitation33.6 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Bonham Rsvr, CO (6 mi away); precipitation: Mesa Lakes, CO (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

816436b

Mesa, CO · 8 mi

814135b

Cedaredge, CO · 11 mi

Battlement Mesa, CO · 23 mi

815207a

Clifton, CO · 23 mi

Colorado planting zones →

Questions about 81646

What planting zone is ZIP code 81646?

ZIP code 81646 (Molina, 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 Molina, CO?

The median last spring frost (32 °F) near 81646 is May 17; after June 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Collbran 1wsw station.

When is the first frost in Molina, CO?

The median first fall frost near 81646 is September 30, giving a median frost-free growing season of 136 days.

When should I plant tomatoes in 81646?

Start tomato seeds indoors around Mar 22 – Apr 5 and set transplants outside around May 24 – Jun 7, one to three weeks after the median last frost.

How much rain and snow does 81646 get?

About 33.6 inches of precipitation a year (NOAA 1991–2020 normals, Mesa Lakes station).

How hot do summers get in Molina, CO?

The average high peaks at 68 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 81646 have?

The USDA soil survey maps Needleton family at the center of ZIP 81646: cobbly loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Molina, CO in 2026?

Spring leaf-out near 81646 came on May 7 in 2026, 11 days later than the 1991–2020 average (Apr 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Molina, CO?

Intermediate onions: the longest day near 81646 is 14 h 55 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 81646 change?

Yes. The 2012 USDA map put 81646 in zone 6b; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.