Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 30, 2026

Planting zone for Montrose, CO

Montrose, CO is in USDA zones 6a to 6b across its 3 ZIP codes. The median last spring frost is April 28 and the first fall frost October 14.

Montrose on the zone map

Outlined: its 2 ZIP code areas · 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.

Zones6a–6b−10 to 0 °F

ZIP codes3

Last frostApr 28

First frostOct 14

Growing season167 days

6a 1 ZIP 6b 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Montrose, 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 Montrose, CO

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 28median — 50% chance of a later frost

Safe for tender plantsMay 12only 10% chance of frost after

First fall frostOctober 14median — 10% chance by Oct 1

Growing season167 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 14 and returns around October 24.

From the NOAA station Montrose #2, CO, elevation 5,791 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 Montrose

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 17 – Mar 31

SpinachSow outdoors · Mar 17 – Apr 7

Broccoli, cabbageStart indoors · Feb 17 – Mar 3

Broccoli, cabbageTransplant · Apr 7 – Apr 21

Onion setsPlant outdoors · Mar 31 – Apr 14

PotatoesPlant outdoors · Apr 7 – Apr 21

LettuceSow outdoors · Mar 31 – Apr 14

Carrots, beetsSow outdoors · Apr 7 – Apr 21

TomatoesStart indoors · Mar 3 – Mar 17

TomatoesTransplant · May 5 – May 19

Peppers, eggplantStart indoors · Feb 17 – Mar 3

Peppers, eggplantTransplant · May 12 – May 26

BeansSow outdoors · May 5 – May 19

Sweet cornSow outdoors · May 5 – May 19

Cucumbers, squashSow outdoors · May 5 – May 19

Fall lettuce, spinachSow outdoors · Aug 19 – Sep 2

GarlicPlant cloves · Sep 30 – Nov 4

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 28) and first fall frost (Oct 14) 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 81402 came on Mar 13 — 15 days earlier than the 1991–2020 average (Mar 28).

average
Mar 282026
Mar 13

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.

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 Montrose, CO.

Soil in Montrose, CO

The center of ZIP 81402 is mapped as Urban land: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

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 81402; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Montrose, CO

Summer high90 °Faverage high, July

Winter low18 °Faverage low, January

Hot days35days a year at 90 °F or more

Freezing nights155nights a year at 32 °F or less

Growing degree days3,044base 50 °F — the season’s usable heat

Longest day14 h 51 mindaylight on June 21

Shortest day9 h 29 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation9.3 inper year, rain and melted snow

Snowfall22 inper year; 36 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Montrose #2, CO (within 1 mile); precipitation: Montrose #2, CO (within 1 mile). Daylight is calculated from latitude.

ZIP codes in Montrose

Colorado planting zones →

Questions about Montrose

What planting zone is Montrose, CO?

Montrose, CO is in USDA hardiness zones 6a to 6b on the 2023 map (6a: −10 to −5 °F; 6b: −5 to 0 °F).

When is the last frost in Montrose, CO?

The median last spring frost is April 28 and the median first fall frost is October 14 (NOAA 1991–2020 normals, Montrose #2 station).

When can I plant a garden in Montrose, CO?

Cool-season crops like peas and spinach go in around Mar 17 – Apr 7; tomatoes, peppers, beans and squash after about May 5, once frost risk has passed.

What kind of onions grow in Montrose, CO?

Intermediate onions: the longest day is 14 h 51 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Montrose, CO get?

About 9.3 inches of precipitation a year and 22 inches of snowfall (NOAA 1991–2020 normals).