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

Planting zone for 80215 — Denver, CO

ZIP code 80215 (Denver, Jefferson County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 3 and the first fall frost October 7.

Where ZIP 80215 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 frostMay 3

First frostOct 7

2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Denver, 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 Denver, CO

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 3median — 50% chance of a later frost

Safe for tender plantsMay 18only 10% chance of frost after

First fall frostOctober 7median — 10% chance by Sep 24

Growing season155 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 22 and returns around October 16.

From the NOAA station Lakewood, CO — within 1 mile, elevation 5,640 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 80215

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 22 – Apr 5

SpinachSow outdoors · Mar 22 – Apr 12

Broccoli, cabbageStart indoors · Feb 22 – Mar 8

Broccoli, cabbageTransplant · Apr 12 – Apr 26

Onion setsPlant outdoors · Apr 5 – Apr 19

PotatoesPlant outdoors · Apr 12 – Apr 26

LettuceSow outdoors · Apr 5 – Apr 19

Carrots, beetsSow outdoors · Apr 12 – Apr 26

TomatoesStart indoors · Mar 8 – Mar 22

TomatoesTransplant · May 10 – May 24

Peppers, eggplantStart indoors · Feb 22 – Mar 8

Peppers, eggplantTransplant · May 17 – May 31

BeansSow outdoors · May 10 – May 24

Sweet cornSow outdoors · May 10 – May 24

Cucumbers, squashSow outdoors · May 10 – May 24

Fall lettuce, spinachSow outdoors · Aug 12 – Aug 26

GarlicPlant cloves · Sep 23 – Oct 28

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 3) and first fall frost (Oct 7) 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 80215 came on Feb 20 — 27 days earlier than the 1991–2020 average (Mar 19).

average
Mar 192026
Feb 20

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 Denver, CO.

Soil in Denver, CO

The soil mapped at the center of ZIP 80215 is Nunn — clay loam, well drained.

TextureClay loamholds water and nutrients; slow to drain and warm up

pH6.7neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3%moderate

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Nunn-Urban land complex, 2 to 5 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 80215; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Denver, CO

Summer high86 °Faverage high, July

Winter low20 °Faverage low, December

Hot days31days a year at 90 °F or more

Freezing nights154nights a year at 32 °F or less

Growing degree days2,713base 50 °F — the season’s usable heat

Longest day14 h 59 mindaylight on June 21

Shortest day9 h 21 mindaylight on December 21

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

Precipitation17.5 inper year, rain and melted snow

Snowfall58 inper year; 47 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: Lakewood, CO (within 1 mile); precipitation: Lakewood, CO (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

800336a

Wheat Ridge, CO · 2 mi

802146a

Denver, CO · 2 mi

800346a

Wheat Ridge, CO · 3 mi

All 59 ZIP codes in Denver → · Colorado planting zones →

Questions about 80215

What planting zone is ZIP code 80215?

ZIP code 80215 (Denver, 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 Denver, CO?

The median last spring frost (32 °F) near 80215 is May 3; after May 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lakewood station.

When is the first frost in Denver, CO?

The median first fall frost near 80215 is October 7, giving a median frost-free growing season of 155 days.

When should I plant tomatoes in 80215?

Start tomato seeds indoors around Mar 8 – Mar 22 and set transplants outside around May 10 – May 24, one to three weeks after the median last frost.

How much rain and snow does 80215 get?

About 17.5 inches of precipitation a year and 58 inches of snowfall (NOAA 1991–2020 normals, Lakewood station).

How hot do summers get in Denver, CO?

The average high peaks at 86 °F in July, with about 31 days a year at 90 °F or more.

What kind of soil does 80215 have?

The USDA soil survey maps Nunn at the center of ZIP 80215: clay loam, well drained, pH about 6.7 (neutral).

Did spring come early in Denver, CO in 2026?

Spring leaf-out near 80215 came on Feb 20 in 2026, 27 days earlier than the 1991–2020 average (Mar 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Denver, CO?

Intermediate onions: the longest day near 80215 is 14 h 59 min, so day-neutral types bulb best; long-day varieties may not bulb fully.