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

Planting zone for 80474 — Rollinsville, CO

ZIP code 80474 (Rollinsville, Gilpin County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is June 21 and the first fall frost September 2.

Where ZIP 80474 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 frostJun 21

First frostSep 2

2012 zone5a

Was 5a on the 2012 map — half a zone warmer 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 Rollinsville, 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 Rollinsville, CO

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostJune 21median — 50% chance of a later frost

Safe for tender plantsJuly 4only 10% chance of frost after

First fall frostSeptember 2median — 10% chance by Aug 17

Growing season71 daysfrost-free, median

A hard freeze (28 °F) usually ends around June 4 and returns around September 14.

From the NOAA station Boulder 14 W, CO — 8 miles away, elevation 9,830 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 80474

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · May 10 – May 24

SpinachSow outdoors · May 10 – May 31

Broccoli, cabbageStart indoors · Apr 12 – Apr 26

Broccoli, cabbageTransplant · May 31 – Jun 14

Onion setsPlant outdoors · May 24 – Jun 7

PotatoesPlant outdoors · May 31 – Jun 14

LettuceSow outdoors · May 24 – Jun 7

Carrots, beetsSow outdoors · May 31 – Jun 14

TomatoesStart indoors · Apr 26 – May 10

TomatoesTransplant · Jun 28 – Jul 12

Peppers, eggplantStart indoors · Apr 12 – Apr 26

Peppers, eggplantTransplant · Jul 5 – Jul 19

BeansSow outdoors · Jun 28 – Jul 12

Sweet cornSow outdoors · Jun 28 – Jul 12

Cucumbers, squashSow outdoors · Jun 28 – Jul 12

Fall lettuce, spinachSow outdoors · Jul 8 – Jul 22

GarlicPlant cloves · Aug 19 – Sep 23

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 21) and first fall frost (Sep 2) 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 80474 came on Apr 15 — 22 days earlier than the 1991–2020 average (May 7).

average
May 72026
Apr 15

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).

Soil in Rollinsville, CO

The soil mapped at the center of ZIP 80474 is Rogert family — very stony sandy loam, somewhat excessively drained.

TextureVery stony sandy loamdrains and warms fast; dries out and needs more feeding

pH6.8neutral; most vegetables like 6.0–7.0

DrainageSomewhat excessively drainednatural drainage class

Organic matter2%moderate

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Rogert family, 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 80474; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Rollinsville, CO

Summer high68 °Faverage high, July

Winter low12 °Faverage low, January

Hot days0days a year at 90 °F or more

Freezing nights244nights a year at 32 °F or less

Growing degree days385base 50 °F — the season’s usable heat

Longest day15 h 00 mindaylight on June 21

Shortest day9 h 20 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation31.1 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: Boulder 14 W, CO (8 mi away); precipitation: Lake Eldora, CO (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

804225b

Black Hawk, CO · 5 mi

804665b

Nederland, CO · 5 mi

804715b

Pinecliffe, CO · 8 mi

804275b

Central City, CO · 9 mi

804365b

Dumont, CO · 11 mi

804825a

Winter Park, CO · 12 mi

Colorado planting zones →

Questions about 80474

What planting zone is ZIP code 80474?

ZIP code 80474 (Rollinsville, 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 Rollinsville, CO?

The median last spring frost (32 °F) near 80474 is June 21; after July 4 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Boulder 14 W station.

When is the first frost in Rollinsville, CO?

The median first fall frost near 80474 is September 2, giving a median frost-free growing season of 71 days.

When should I plant tomatoes in 80474?

Start tomato seeds indoors around Apr 26 – May 10 and set transplants outside around Jun 28 – Jul 12, one to three weeks after the median last frost.

How much rain and snow does 80474 get?

About 31.1 inches of precipitation a year (NOAA 1991–2020 normals, Lake Eldora station).

How hot do summers get in Rollinsville, 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 80474 have?

The USDA soil survey maps Rogert family at the center of ZIP 80474: very stony sandy loam, somewhat excessively drained, pH about 6.8 (neutral).

Did spring come early in Rollinsville, CO in 2026?

Spring leaf-out near 80474 came on Apr 15 in 2026, 22 days earlier than the 1991–2020 average (May 7), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Rollinsville, CO?

Long-day onions: the longest day near 80474 is 15 h 00 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 80474 change?

Yes. The 2012 USDA map put 80474 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.