Planting zone for 81090 — Walsh, CO
ZIP code 81090 (Walsh, Baca County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 30 and the first fall frost October 14.
Where ZIP 81090 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
Was 6a 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 6b means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Walsh, 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 Walsh, CO
A hard freeze (28 °F) usually ends around April 19 and returns around October 22.
From the NOAA station Walsh 1 W, CO — 4 miles away, elevation 3,980 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 81090
Counted from the median last spring frost (Apr 30) 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 81090 came on Feb 19 — 20 days earlier than the 1991–2020 average (Mar 11).
Mar 112026
Feb 19
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 6b in Colorado
565 plants native to the lower 48 states, recorded in Colorado, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.
Trees 28
Shrubs 104
Wildflowers & perennials 252
Grasses 168
Vines 4
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 Walsh, CO.
Soil in Walsh, CO
The soil mapped at the center of ZIP 81090 is Wiley — loam, well drained.
Map unit: Wiley loam, 1 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 81090; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Walsh, CO
Average high and low, by month
Precipitation by month inches · ❄ = snowfall
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Walsh 1 W, CO (4 mi away); precipitation: Walsh 1 W, CO (4 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
All 8 nearest ZIP codes share zone 6b.
Questions about 81090
What planting zone is ZIP code 81090?
ZIP code 81090 (Walsh, CO) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).
When is the last frost in Walsh, CO?
The median last spring frost (32 °F) near 81090 is April 30; after May 12 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Walsh 1 W station.
When is the first frost in Walsh, CO?
The median first fall frost near 81090 is October 14, giving a median frost-free growing season of 166 days.
When should I plant tomatoes in 81090?
Start tomato seeds indoors around Mar 5 – Mar 19 and set transplants outside around May 7 – May 21, one to three weeks after the median last frost.
How much rain and snow does 81090 get?
About 19.5 inches of precipitation a year and 23 inches of snowfall (NOAA 1991–2020 normals, Walsh 1 W station).
How hot do summers get in Walsh, CO?
The average high peaks at 93 °F in July, with about 69 days a year at 90 °F or more.
What kind of soil does 81090 have?
The USDA soil survey maps Wiley at the center of ZIP 81090: loam, well drained, pH about 7.9 (alkaline).
Did spring come early in Walsh, CO in 2026?
Spring leaf-out near 81090 came on Feb 19 in 2026, 20 days earlier than the 1991–2020 average (Mar 11), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Walsh, CO?
Intermediate onions: the longest day near 81090 is 14 h 44 min, so day-neutral types bulb best; long-day varieties may not bulb fully.
Did the zone for 81090 change?
Yes. The 2012 USDA map put 81090 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.