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

Planting zone for 97345 — Foster, OR

ZIP code 97345 (Foster, Linn County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 12 and the first fall frost October 28.

Where ZIP 97345 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 12
First frostOct 28
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 Foster, 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 Foster, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 12median — 50% chance of a later frost
Safe for tender plantsMay 5only 10% chance of frost after
First fall frostOctober 28median — 10% chance by Oct 5
Growing season197 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 9 and returns around November 18.

From the NOAA station Foster Dam, OR — 4 miles away, elevation 551 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 97345

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 1 – Mar 15
SpinachSow outdoors · Mar 1 – Mar 22
Broccoli, cabbageStart indoors · Feb 1 – Feb 15
Broccoli, cabbageTransplant · Mar 22 – Apr 5
Onion setsPlant outdoors · Mar 15 – Mar 29
PotatoesPlant outdoors · Mar 22 – Apr 5
LettuceSow outdoors · Mar 15 – Mar 29
Carrots, beetsSow outdoors · Mar 22 – Apr 5
TomatoesStart indoors · Feb 15 – Mar 1
TomatoesTransplant · Apr 19 – May 3
Peppers, eggplantStart indoors · Feb 1 – Feb 15
Peppers, eggplantTransplant · Apr 26 – May 10
BeansSow outdoors · Apr 19 – May 3
Sweet cornSow outdoors · Apr 19 – May 3
Cucumbers, squashSow outdoors · Apr 19 – May 3
Fall lettuce, spinachSow outdoors · Sep 2 – Sep 16
GarlicPlant cloves · Oct 14 – Nov 18
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 28) 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 97345 came on Feb 13 — 11 days earlier than the 1991–2020 average (Feb 24).

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 Foster, OR.

Soil in Foster, OR

The soil mapped at the center of ZIP 97345 is Honeygrove — 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 groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Honeygrove silty clay loam, 12 to 25 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 97345; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Foster, OR

Summer high83 °Faverage high, August
Winter low34 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights55nights a year at 32 °F or less
Growing degree days2,111base 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)
Precipitation54.5 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 48 °F, low 34 °F 48°34° JanFebruary: average high 51 °F, low 35 °F 51°35° FebMarch: average high 56 °F, low 37 °F 56°37° MarApril: average high 60 °F, low 40 °F 60°40° AprMay: average high 67 °F, low 44 °F 67°44° MayJune: average high 73 °F, low 48 °F 73°48° JunJuly: average high 82 °F, low 51 °F 82°51° JulAugust: average high 83 °F, low 50 °F 83°50° AugSeptember: average high 76 °F, low 47 °F 76°47° SepOctober: average high 64 °F, low 42 °F 64°42° OctNovember: average high 53 °F, low 38 °F 53°38° NovDecember: average high 47 °F, low 34 °F 47°34° Dec

Precipitation by month inches

0″2″4″6″8″January: 7.15 in precipitation, 0.1 in snowfall 7.2 JanFebruary: 5.56 in precipitation 5.6 FebMarch: 6.26 in precipitation 6.3 MarApril: 5.37 in precipitation 5.4 AprMay: 3.80 in precipitation 3.8 MayJune: 2.46 in precipitation 2.5 JunJuly: 0.54 in precipitation 0.5 JulAugust: 0.64 in precipitation 0.6 AugSeptember: 1.99 in precipitation 2.0 SepOctober: 4.64 in precipitation 4.6 OctNovember: 7.64 in precipitation 7.6 NovDecember: 8.40 in precipitation 8.4 Dec

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

973868b
Sweet Home, OR · 8 mi
973368b
Crawfordsville, OR · 14 mi
973298b
Cascadia, OR · 15 mi
973558b
Lebanon, OR · 15 mi
974548b
Marcola, OR · 18 mi
973278b
Brownsville, OR · 18 mi
974898b
Walterville, OR · 21 mi
974888b
Vida, OR · 21 mi

Oregon planting zones →

Questions about 97345

What planting zone is ZIP code 97345?

ZIP code 97345 (Foster, 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 Foster, OR?

The median last spring frost (32 °F) near 97345 is April 12; after May 5 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Foster Dam station.

When is the first frost in Foster, OR?

The median first fall frost near 97345 is October 28, giving a median frost-free growing season of 197 days.

When should I plant tomatoes in 97345?

Start tomato seeds indoors around Feb 15 – Mar 1 and set transplants outside around Apr 19 – May 3, one to three weeks after the median last frost.

How much rain and snow does 97345 get?

About 54.5 inches of precipitation a year (NOAA 1991–2020 normals, Foster Dam station).

How hot do summers get in Foster, OR?

The average high peaks at 83 °F in August, with about 17 days a year at 90 °F or more.

What kind of soil does 97345 have?

The USDA soil survey maps Honeygrove at the center of ZIP 97345: slightly decomposed plant material, well drained, pH about 4.5 (strongly acidic).

Did spring come early in Foster, OR in 2026?

Spring leaf-out near 97345 came on Feb 13 in 2026, 11 days earlier than the 1991–2020 average (Feb 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Foster, OR?

Long-day onions: the longest day near 97345 is 15 h 32 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).