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

Planting zone for 98291 — Snohomish, WA

ZIP code 98291 (Snohomish, Snohomish County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 17 and the first fall frost October 23.

Where ZIP 98291 is

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.

Zone8b15 to 20 °F
Coldest night−9.4 to −6.7 °C
Last frostApr 17
First frostOct 23
2012 zone8b

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 8b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Snohomish, 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 Snohomish, WA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 17median — 50% chance of a later frost
Safe for tender plantsMay 7only 10% chance of frost after
First fall frostOctober 23median — 10% chance by Oct 7
Growing season188 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 26 and returns around November 8.

From the NOAA station Monroe, WA — 5 miles away, elevation 121 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 98291

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 6 – Mar 20
SpinachSow outdoors · Mar 6 – Mar 27
Broccoli, cabbageStart indoors · Feb 6 – Feb 20
Broccoli, cabbageTransplant · Mar 27 – Apr 10
Onion setsPlant outdoors · Mar 20 – Apr 3
PotatoesPlant outdoors · Mar 27 – Apr 10
LettuceSow outdoors · Mar 20 – Apr 3
Carrots, beetsSow outdoors · Mar 27 – Apr 10
TomatoesStart indoors · Feb 20 – Mar 6
TomatoesTransplant · Apr 24 – May 8
Peppers, eggplantStart indoors · Feb 6 – Feb 20
Peppers, eggplantTransplant · May 1 – May 15
BeansSow outdoors · Apr 24 – May 8
Sweet cornSow outdoors · Apr 24 – May 8
Cucumbers, squashSow outdoors · Apr 24 – May 8
Fall lettuce, spinachSow outdoors · Aug 28 – Sep 11
GarlicPlant cloves · Oct 9 – Nov 13
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 17) and first fall frost (Oct 23) 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 98291 came on Feb 20 — about the same time as the 1991–2020 average (Feb 21).

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 8b in Washington

614 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 15 °F or colder — the bottom of zone 8b. Each links to its USDA PLANTS profile.

Trees 32

Alaska cedar75 ft · blooms mid spring · low shade tolerance · to −22 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fbigleaf maple60 ft · blooms mid spring · medium shade tolerance · to −14 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fboxelder60 ft · blooms early spring · low shade tolerance · to −46 °F

Shrubs 114

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °FBarclay's willow15 ft · high shade tolerance · to −43 °F

Wildflowers & perennials 293

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bistort1.5 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °F

Grasses 157

Alaska brome5 ft · blooms late spring · low shade tolerance · to −18 °FAlaska oniongrass3 ft · blooms mid spring · low shade tolerance · to −33 °Falkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °FAmerican beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °F

Vines 3

riverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °Fwestern white clematis1 ft · blooms mid summer · medium shade tolerance · to −38 °F

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 Snohomish, WA.

Soil in Snohomish, WA

The soil mapped at the center of ZIP 98291 is Tokul — slightly decomposed plant material, moderately well drained.

TextureSlightly decomposed plant materialtop layer
pH4.5strongly acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter75%high
Hydrologic groupBwater soaks in moderately
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Tokul gravelly medial loam, 15 to 30 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 98291; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Snohomish, WA

Summer high75 °Faverage high, August
Winter low32 °Faverage low, January
Hot days2days a year at 90 °F or more
Freezing nights60nights a year at 32 °F or less
Growing degree days1,550base 50 °F — the season’s usable heat
Longest day16 h 02 mindaylight on June 21
Shortest day8 h 23 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation50.8 inper year, rain and melted snow
Snowfall3 inper year; 3 days with snow on the ground

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 44 °F, low 32 °F 44°32° JanFebruary: average high 48 °F, low 32 °F 48°32° FebMarch: average high 52 °F, low 35 °F 52°35° MarApril: average high 57 °F, low 39 °F 57°39° AprMay: average high 64 °F, low 44 °F 64°44° MayJune: average high 68 °F, low 49 °F 68°49° JunJuly: average high 74 °F, low 52 °F 74°52° JulAugust: average high 75 °F, low 52 °F 75°52° AugSeptember: average high 69 °F, low 48 °F 69°48° SepOctober: average high 58 °F, low 41 °F 58°41° OctNovember: average high 49 °F, low 35 °F 49°35° NovDecember: average high 43 °F, low 32 °F 43°32° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″8″January: 6.54 in precipitation, 0.1 in snowfall 6.5 JanFebruary: 4.47 in precipitation, 2.2 in snowfall 4.5❄2 FebMarch: 5.22 in precipitation, 0.2 in snowfall 5.2 MarApril: 4.30 in precipitation 4.3 AprMay: 3.42 in precipitation 3.4 MayJune: 2.69 in precipitation 2.7 JunJuly: 1.15 in precipitation 1.1 JulAugust: 1.30 in precipitation 1.3 AugSeptember: 2.73 in precipitation 2.7 SepOctober: 5.03 in precipitation 5.0 OctNovember: 7.16 in precipitation, 0.3 in snowfall 7.2 NovDecember: 6.76 in precipitation, 0.2 in snowfall 6.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Monroe, WA (5 mi away); precipitation: Monroe, WA (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

982908b
Snohomish, WA · 5 mi
982968b
Snohomish, WA · 5 mi
982088b
Everett, WA · 6 mi
980828b
Mill Creek, WA · 8 mi
980128b
Bothell, WA · 8 mi
982728b
Monroe, WA · 8 mi
982138b
Everett, WA · 9 mi
982018b
Everett, WA · 9 mi

All 3 ZIP codes in Snohomish → · Washington planting zones →

Questions about 98291

What planting zone is ZIP code 98291?

ZIP code 98291 (Snohomish, WA) is in USDA hardiness zone 8b on the 2023 map: the coldest night of an average winter reaches 15 to 20 °F (−9.4 to −6.7 °C).

When is the last frost in Snohomish, WA?

The median last spring frost (32 °F) near 98291 is April 17; after May 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Monroe station.

When is the first frost in Snohomish, WA?

The median first fall frost near 98291 is October 23, giving a median frost-free growing season of 188 days.

When should I plant tomatoes in 98291?

Start tomato seeds indoors around Feb 20 – Mar 6 and set transplants outside around Apr 24 – May 8, one to three weeks after the median last frost.

How much rain and snow does 98291 get?

About 50.8 inches of precipitation a year and 3 inches of snowfall (NOAA 1991–2020 normals, Monroe station).

How hot do summers get in Snohomish, WA?

The average high peaks at 75 °F in August, with about 2 days a year at 90 °F or more.

What kind of soil does 98291 have?

The USDA soil survey maps Tokul at the center of ZIP 98291: slightly decomposed plant material, moderately well drained, pH about 4.5 (strongly acidic).

Did spring come early in Snohomish, WA in 2026?

Spring leaf-out near 98291 came on Feb 20 in 2026, about the same as the 1991–2020 average (Feb 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Snohomish, WA?

Long-day onions: the longest day near 98291 is 16 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).