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

Planting zone for 97140 — Sherwood, OR

ZIP code 97140 (Sherwood, Washington County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 21 and the first fall frost November 22.

Where ZIP 97140 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.

Zone8b15 to 20 °F
Coldest night−9.4 to −6.7 °C
Last frostMar 21
First frostNov 22
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 Sherwood, OR…

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 Sherwood, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 21median — 50% chance of a later frost
Safe for tender plantsApril 19only 10% chance of frost after
First fall frostNovember 22median — 10% chance by Nov 4
Growing season241 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 15 and returns around December 10.

From the NOAA station Rex 1 S, OR — 4 miles away, elevation 515 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 97140

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 7 – Feb 21
SpinachSow outdoors · Feb 7 – Feb 28
Broccoli, cabbageStart indoors · Jan 10 – Jan 24
Broccoli, cabbageTransplant · Feb 28 – Mar 14
Onion setsPlant outdoors · Feb 21 – Mar 7
PotatoesPlant outdoors · Feb 28 – Mar 14
LettuceSow outdoors · Feb 21 – Mar 7
Carrots, beetsSow outdoors · Feb 28 – Mar 14
TomatoesStart indoors · Jan 24 – Feb 7
TomatoesTransplant · Mar 28 – Apr 11
Peppers, eggplantStart indoors · Jan 10 – Jan 24
Peppers, eggplantTransplant · Apr 4 – Apr 18
BeansSow outdoors · Mar 28 – Apr 11
Sweet cornSow outdoors · Mar 28 – Apr 11
Cucumbers, squashSow outdoors · Mar 28 – Apr 11
Fall lettuce, spinachSow outdoors · Sep 27 – Oct 11
GarlicPlant cloves · Nov 8 – Dec 13
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 21) and first fall frost (Nov 22) 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 97140 came on Feb 16 — 4 days earlier than the 1991–2020 average (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 8b in Oregon

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

Trees 43

Alaska cedar75 ft · blooms mid spring · low shade tolerance · to −22 °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 °FBrewer spruce100 ft · blooms early summer · low shade tolerance · to −13 °F

Shrubs 132

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °Falderleaf mountain mahogany15 ft · blooms late spring · medium shade tolerance · to −41 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °Fbeaked hazelnut15 ft · blooms early spring · low shade tolerance · to −47 °Fbig sagebrush4 ft · blooms mid summer · high shade tolerance · to −43 °F

Wildflowers & perennials 305

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 166

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 2

riverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °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 Sherwood, OR.

Soil in Sherwood, OR

The soil mapped at the center of ZIP 97140 is Aloha — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables
pH5.8moderately acidic; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2.5%moderate
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Aloha silt loam.

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 97140; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sherwood, OR

Summer high81 °Faverage high, July
Winter low34 °Faverage low, December
Hot days15days a year at 90 °F or more
Freezing nights43nights a year at 32 °F or less
Growing degree days2,381base 50 °F — the season’s usable heat
Longest day15 h 40 mindaylight on June 21
Shortest day8 h 43 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation44.2 inper year, rain and melted snow
Snowfall1 inper year

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 45 °F, low 35 °F 45°35° JanFebruary: average high 50 °F, low 36 °F 50°36° FebMarch: average high 55 °F, low 38 °F 55°38° MarApril: average high 61 °F, low 41 °F 61°41° AprMay: average high 66 °F, low 47 °F 66°47° MayJune: average high 72 °F, low 51 °F 72°51° JunJuly: average high 81 °F, low 56 °F 81°56° JulAugust: average high 81 °F, low 56 °F 81°56° AugSeptember: average high 75 °F, low 52 °F 75°52° SepOctober: average high 62 °F, low 45 °F 62°45° OctNovember: average high 51 °F, low 39 °F 51°39° NovDecember: average high 44 °F, low 34 °F 44°34° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″8″January: 6.38 in precipitation, 0.6 in snowfall 6.4❄1 JanFebruary: 4.56 in precipitation, 0.1 in snowfall 4.6 FebMarch: 4.77 in precipitation, 0.2 in snowfall 4.8 MarApril: 3.56 in precipitation 3.6 AprMay: 2.57 in precipitation 2.6 MayJune: 1.58 in precipitation 1.6 JunJuly: 0.43 in precipitation 0.4 JulAugust: 0.55 in precipitation 0.6 AugSeptember: 1.63 in precipitation 1.6 SepOctober: 4.17 in precipitation 4.2 OctNovember: 6.65 in precipitation 6.7 NovDecember: 7.37 in precipitation, 0.1 in snowfall 7.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Rex 1 S, OR (4 mi away); precipitation: Rex 1 S, OR (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

972249a
Portland, OR · 5 mi
970629a
Tualatin, OR · 5 mi
970708b
Wilsonville, OR · 6 mi
970078b
Beaverton, OR · 6 mi
971328b
Newberg, OR · 6 mi
972239a
Portland, OR · 7 mi
970799a
Beaverton, OR · 8 mi
970359a
Lake Oswego, OR · 8 mi

Oregon planting zones →

Questions about 97140

What planting zone is ZIP code 97140?

ZIP code 97140 (Sherwood, OR) 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 Sherwood, OR?

The median last spring frost (32 °F) near 97140 is March 21; after April 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Rex 1 S station.

When is the first frost in Sherwood, OR?

The median first fall frost near 97140 is November 22, giving a median frost-free growing season of 241 days.

When should I plant tomatoes in 97140?

Start tomato seeds indoors around Jan 24 – Feb 7 and set transplants outside around Mar 28 – Apr 11, one to three weeks after the median last frost.

How much rain and snow does 97140 get?

About 44.2 inches of precipitation a year and 1 inches of snowfall (NOAA 1991–2020 normals, Rex 1 S station).

How hot do summers get in Sherwood, OR?

The average high peaks at 81 °F in July, with about 15 days a year at 90 °F or more.

What kind of soil does 97140 have?

The USDA soil survey maps Aloha at the center of ZIP 97140: silt loam, somewhat poorly drained, pH about 5.8 (moderately acidic).

Did spring come early in Sherwood, OR in 2026?

Spring leaf-out near 97140 came on Feb 16 in 2026, 4 days earlier than the 1991–2020 average (Feb 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sherwood, OR?

Long-day onions: the longest day near 97140 is 15 h 40 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).