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

Planting zone for 97329 — Cascadia, OR

ZIP code 97329 (Cascadia, Linn County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 29 and the first fall frost October 13.

Where ZIP 97329 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 frostApr 29
First frostOct 13
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 Cascadia, 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 Cascadia, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 29median — 50% chance of a later frost
Safe for tender plantsMay 17only 10% chance of frost after
First fall frostOctober 13median — 10% chance by Sep 22
Growing season167 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 30 and returns around November 5.

From the NOAA station Cascadia, OR — 9 miles away, elevation 961 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 97329

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 18 – Apr 1
SpinachSow outdoors · Mar 18 – Apr 8
Broccoli, cabbageStart indoors · Feb 18 – Mar 4
Broccoli, cabbageTransplant · Apr 8 – Apr 22
Onion setsPlant outdoors · Apr 1 – Apr 15
PotatoesPlant outdoors · Apr 8 – Apr 22
LettuceSow outdoors · Apr 1 – Apr 15
Carrots, beetsSow outdoors · Apr 8 – Apr 22
TomatoesStart indoors · Mar 4 – Mar 18
TomatoesTransplant · May 6 – May 20
Peppers, eggplantStart indoors · Feb 18 – Mar 4
Peppers, eggplantTransplant · May 13 – May 27
BeansSow outdoors · May 6 – May 20
Sweet cornSow outdoors · May 6 – May 20
Cucumbers, squashSow outdoors · May 6 – May 20
Fall lettuce, spinachSow outdoors · Aug 18 – Sep 1
GarlicPlant cloves · Sep 29 – Nov 3
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 29) and first fall frost (Oct 13) 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 97329 came on Feb 16 — 47 days earlier than the 1991–2020 average (Apr 4).

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 Cascadia, OR.

Soil in Cascadia, OR

The soil mapped at the center of ZIP 97329 is Idanha — 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 groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Idanha, moist-Icecap complex, 45 to 70 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 97329; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cascadia, OR

Summer high80 °Faverage high, August
Winter low33 °Faverage low, January
Hot days8days a year at 90 °F or more
Freezing nights79nights a year at 32 °F or less
Growing degree days1,647base 50 °F — the season’s usable heat
Longest day15 h 32 mindaylight on June 21
Shortest day8 h 50 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation85.2 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 45 °F, low 33 °F 45°33° JanFebruary: average high 50 °F, low 33 °F 50°33° FebMarch: average high 54 °F, low 34 °F 54°34° MarApril: average high 58 °F, low 37 °F 58°37° AprMay: average high 65 °F, low 42 °F 65°42° MayJune: average high 70 °F, low 46 °F 70°46° JunJuly: average high 79 °F, low 49 °F 79°49° JulAugust: average high 80 °F, low 48 °F 80°48° AugSeptember: average high 74 °F, low 44 °F 74°44° SepOctober: average high 62 °F, low 39 °F 62°39° OctNovember: average high 50 °F, low 35 °F 50°35° NovDecember: average high 44 °F, low 33 °F 44°33° Dec

Precipitation by month inches

0″2″4″6″8″10″12″14″January: 11.39 in precipitation 11.4 JanFebruary: 8.84 in precipitation 8.8 FebMarch: 9.55 in precipitation 9.6 MarApril: 7.91 in precipitation 7.9 AprMay: 5.35 in precipitation 5.3 MayJune: 3.82 in precipitation 3.8 JunJuly: 0.57 in precipitation 0.6 JulAugust: 0.95 in precipitation 0.9 AugSeptember: 2.90 in precipitation 2.9 SepOctober: 7.30 in precipitation 7.3 OctNovember: 12.42 in precipitation 12.4 NovDecember: 14.23 in precipitation 14.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cascadia, OR (9 mi away); precipitation: Jump Off Joe, OR (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

973458b
Foster, OR · 15 mi
974888b
Vida, OR · 18 mi
973868b
Sweet Home, OR · 22 mi
974898b
Walterville, OR · 24 mi
973507b
Idanha, OR · 25 mi
977597a
Sisters, OR · 27 mi
973368b
Crawfordsville, OR · 28 mi
974137b
Blue River, OR · 28 mi

Oregon planting zones →

Questions about 97329

What planting zone is ZIP code 97329?

ZIP code 97329 (Cascadia, 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 Cascadia, OR?

The median last spring frost (32 °F) near 97329 is April 29; after May 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cascadia station.

When is the first frost in Cascadia, OR?

The median first fall frost near 97329 is October 13, giving a median frost-free growing season of 167 days.

When should I plant tomatoes in 97329?

Start tomato seeds indoors around Mar 4 – Mar 18 and set transplants outside around May 6 – May 20, one to three weeks after the median last frost.

How much rain and snow does 97329 get?

About 85.2 inches of precipitation a year (NOAA 1991–2020 normals, Jump Off Joe station).

How hot do summers get in Cascadia, OR?

The average high peaks at 80 °F in August, with about 8 days a year at 90 °F or more.

What kind of soil does 97329 have?

The USDA soil survey maps Idanha at the center of ZIP 97329: slightly decomposed plant material, well drained, pH about 4.5 (strongly acidic).

Did spring come early in Cascadia, OR in 2026?

Spring leaf-out near 97329 came on Feb 16 in 2026, 47 days earlier than the 1991–2020 average (Apr 4), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cascadia, OR?

Long-day onions: the longest day near 97329 is 15 h 32 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).