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

Planting zone for 97103 — Astoria, OR

ZIP code 97103 (Astoria, Clatsop County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 30 and the first fall frost November 18.

Where ZIP 97103 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 30
First frostNov 18
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 Astoria, 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 Astoria, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 30median — 50% chance of a later frost
Safe for tender plantsApril 28only 10% chance of frost after
First fall frostNovember 18median — 10% chance by Oct 27
Growing season233 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 12 and returns around December 13.

From the NOAA station Ft Clatsop Natl Mem, OR — 9 miles away, elevation 43 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 97103

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 16 – Mar 2
SpinachSow outdoors · Feb 16 – Mar 9
Broccoli, cabbageStart indoors · Jan 19 – Feb 2
Broccoli, cabbageTransplant · Mar 9 – Mar 23
Onion setsPlant outdoors · Mar 2 – Mar 16
PotatoesPlant outdoors · Mar 9 – Mar 23
LettuceSow outdoors · Mar 2 – Mar 16
Carrots, beetsSow outdoors · Mar 9 – Mar 23
TomatoesStart indoors · Feb 2 – Feb 16
TomatoesTransplant · Apr 6 – Apr 20
Peppers, eggplantStart indoors · Jan 19 – Feb 2
Peppers, eggplantTransplant · Apr 13 – Apr 27
BeansSow outdoors · Apr 6 – Apr 20
Sweet cornSow outdoors · Apr 6 – Apr 20
Cucumbers, squashSow outdoors · Apr 6 – Apr 20
Fall lettuce, spinachSow outdoors · Sep 23 – Oct 7
GarlicPlant cloves · Nov 4 – Dec 9
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 30) and first fall frost (Nov 18) 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 97103 came on Feb 3 — 16 days earlier than the 1991–2020 average (Feb 19).

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 Astoria, OR.

Soil in Astoria, OR

The soil mapped at the center of ZIP 97103 is Svensen — 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: Svensen medial loam, 30 to 60 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 97103; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Astoria, OR

Summer high71 °Faverage high, August
Winter low37 °Faverage low, February
Hot days1days a year at 90 °F or more
Freezing nights31nights a year at 32 °F or less
Growing degree days1,614base 50 °F — the season’s usable heat
Longest day15 h 46 mindaylight on June 21
Shortest day8 h 37 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation70.3 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°32 °FJanuary: average high 49 °F, low 38 °F 49°38° JanFebruary: average high 51 °F, low 37 °F 51°37° FebMarch: average high 54 °F, low 39 °F 54°39° MarApril: average high 58 °F, low 41 °F 58°41° AprMay: average high 64 °F, low 45 °F 64°45° MayJune: average high 67 °F, low 49 °F 67°49° JunJuly: average high 70 °F, low 53 °F 70°53° JulAugust: average high 71 °F, low 53 °F 71°53° AugSeptember: average high 70 °F, low 49 °F 70°49° SepOctober: average high 61 °F, low 45 °F 61°45° OctNovember: average high 53 °F, low 40 °F 53°40° NovDecember: average high 49 °F, low 37 °F 49°37° Dec

Precipitation by month inches

0″2″4″6″8″10″12″January: 10.59 in precipitation 10.6 JanFebruary: 7.18 in precipitation 7.2 FebMarch: 7.90 in precipitation 7.9 MarApril: 5.80 in precipitation 5.8 AprMay: 3.40 in precipitation 3.4 MayJune: 2.30 in precipitation 2.3 JunJuly: 0.83 in precipitation 0.8 JulAugust: 1.12 in precipitation 1.1 AugSeptember: 2.67 in precipitation 2.7 SepOctober: 6.74 in precipitation 6.7 OctNovember: 11.05 in precipitation 11.1 NovDecember: 10.68 in precipitation 10.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Ft Clatsop Natl Mem, OR (9 mi away); precipitation: Astoria Regional Airport, OR (9 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.

971469a
Warrenton, OR · 10 mi
986438b
Rosburg, WA · 11 mi
971219a
Hammond, OR · 14 mi
986148b
Chinook, WA · 15 mi
971388b
Seaside, OR · 16 mi
986388b
Naselle, WA · 18 mi
986478b
Skamokawa, WA · 19 mi
986249a
Ilwaco, WA · 19 mi

Oregon planting zones →

Questions about 97103

What planting zone is ZIP code 97103?

ZIP code 97103 (Astoria, 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 Astoria, OR?

The median last spring frost (32 °F) near 97103 is March 30; after April 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Ft Clatsop Natl Mem station.

When is the first frost in Astoria, OR?

The median first fall frost near 97103 is November 18, giving a median frost-free growing season of 233 days.

When should I plant tomatoes in 97103?

Start tomato seeds indoors around Feb 2 – Feb 16 and set transplants outside around Apr 6 – Apr 20, one to three weeks after the median last frost.

How much rain and snow does 97103 get?

About 70.3 inches of precipitation a year (NOAA 1991–2020 normals, Astoria Regional Airport station).

How hot do summers get in Astoria, OR?

The average high peaks at 71 °F in August, with about 1 days a year at 90 °F or more.

What kind of soil does 97103 have?

The USDA soil survey maps Svensen at the center of ZIP 97103: slightly decomposed plant material, well drained, pH about 4.5 (strongly acidic).

Did spring come early in Astoria, OR in 2026?

Spring leaf-out near 97103 came on Feb 3 in 2026, 16 days earlier than the 1991–2020 average (Feb 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Astoria, OR?

Long-day onions: the longest day near 97103 is 15 h 46 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).