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

Planting zone for 98267 — Marblemount, WA

ZIP code 98267 (Marblemount, Skagit County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 16 and the first fall frost October 25.

Where ZIP 98267 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.

Zone7a0 to 5 °F

Coldest night−17.8 to −15 °C

Last frostApr 16

First frostOct 25

2012 zone8a

Was 8a 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Marblemount, WA…

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 Marblemount, WA

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 16median — 50% chance of a later frost

Safe for tender plantsMay 6only 10% chance of frost after

First fall frostOctober 25median — 10% chance by Oct 10

Growing season192 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 19 and returns around November 11.

From the NOAA station Darrington 21 Nne, WA — 13 miles away, elevation 407 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 98267

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 5 – Mar 19

SpinachSow outdoors · Mar 5 – Mar 26

Broccoli, cabbageStart indoors · Feb 5 – Feb 19

Broccoli, cabbageTransplant · Mar 26 – Apr 9

Onion setsPlant outdoors · Mar 19 – Apr 2

PotatoesPlant outdoors · Mar 26 – Apr 9

LettuceSow outdoors · Mar 19 – Apr 2

Carrots, beetsSow outdoors · Mar 26 – Apr 9

TomatoesStart indoors · Feb 19 – Mar 5

TomatoesTransplant · Apr 23 – May 7

Peppers, eggplantStart indoors · Feb 5 – Feb 19

Peppers, eggplantTransplant · Apr 30 – May 14

BeansSow outdoors · Apr 23 – May 7

Sweet cornSow outdoors · Apr 23 – May 7

Cucumbers, squashSow outdoors · Apr 23 – May 7

Fall lettuce, spinachSow outdoors · Aug 30 – Sep 13

GarlicPlant cloves · Oct 11 – Nov 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 16) and first fall frost (Oct 25) 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 98267 came on Apr 30 — 9 days earlier than the 1991–2020 average (May 9).

average
May 92026
Apr 30

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 7a in Washington

590 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. 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 Marblemount, WA.

Soil in Marblemount, WA

The soil mapped at the center of ZIP 98267 is Lithic Dystrocryepts — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer

pH4.5strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter75%high

Hydrologic groupDwater soaks in very slowly

Map unit: Rock outcrop-Lithic Dystrocryepts-Glaciers association, 35 to 100 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 98267; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Marblemount, WA

Summer high78 °Faverage high, August

Winter low32 °Faverage low, January

Hot days7days a year at 90 °F or more

Freezing nights79nights a year at 32 °F or less

Growing degree days1,740base 50 °F — the season’s usable heat

Longest day16 h 06 mindaylight on June 21

Shortest day8 h 19 mindaylight on December 21

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

Precipitation83 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: Darrington 21 Nne, WA (13 mi away); precipitation: Darrington 21 Nne, WA (13 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.

982418a

Darrington, WA · 14 mi

Granite Falls, WA · 31 mi

982238b

Arlington, WA · 34 mi

Washington planting zones →

Questions about 98267

What planting zone is ZIP code 98267?

ZIP code 98267 (Marblemount, WA) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Marblemount, WA?

The median last spring frost (32 °F) near 98267 is April 16; after May 6 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Darrington 21 Nne station.

When is the first frost in Marblemount, WA?

The median first fall frost near 98267 is October 25, giving a median frost-free growing season of 192 days.

When should I plant tomatoes in 98267?

Start tomato seeds indoors around Feb 19 – Mar 5 and set transplants outside around Apr 23 – May 7, one to three weeks after the median last frost.

How much rain and snow does 98267 get?

About 83 inches of precipitation a year (NOAA 1991–2020 normals, Darrington 21 Nne station).

How hot do summers get in Marblemount, WA?

The average high peaks at 78 °F in August, with about 7 days a year at 90 °F or more.

What kind of soil does 98267 have?

The USDA soil survey maps Lithic Dystrocryepts at the center of ZIP 98267: slightly decomposed plant material, well drained, pH about 4.5 (strongly acidic).

Did spring come early in Marblemount, WA in 2026?

Spring leaf-out near 98267 came on Apr 30 in 2026, 9 days earlier than the 1991–2020 average (May 9), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Marblemount, WA?

Long-day onions: the longest day near 98267 is 16 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 98267 change?

Yes. The 2012 USDA map put 98267 in zone 8a; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.