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

Planting zone for 97232 — Portland, OR

ZIP code 97232 (Portland, Multnomah County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 25 and the first fall frost December 1.

Where ZIP 97232 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.

Zone9a20 to 25 °F
Coldest night−6.7 to −3.9 °C
Last frostFeb 25
First frostDec 1
2012 zone8b

Was 8b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Portland, 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 Portland, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 25median — 50% chance of a later frost
Safe for tender plantsMarch 21only 10% chance of frost after
First fall frostDecember 1median — 10% chance by Nov 10
Growing season280 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 31 and returns around December 20.

From the NOAA station Portland Kgw-Tv, OR — 2 miles away, elevation 161 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 97232

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 14 – Jan 28
SpinachSow outdoors · Jan 14 – Feb 4
Broccoli, cabbageStart indoors · Dec 17 – Dec 31
Broccoli, cabbageTransplant · Feb 4 – Feb 18
Onion setsPlant outdoors · Jan 28 – Feb 11
PotatoesPlant outdoors · Feb 4 – Feb 18
LettuceSow outdoors · Jan 28 – Feb 11
Carrots, beetsSow outdoors · Feb 4 – Feb 18
TomatoesStart indoors · Dec 31 – Jan 14
TomatoesTransplant · Mar 4 – Mar 18
Peppers, eggplantStart indoors · Dec 17 – Dec 31
Peppers, eggplantTransplant · Mar 11 – Mar 25
BeansSow outdoors · Mar 4 – Mar 18
Sweet cornSow outdoors · Mar 4 – Mar 18
Cucumbers, squashSow outdoors · Mar 4 – Mar 18
Fall lettuce, spinachSow outdoors · Oct 6 – Oct 20
GarlicPlant cloves · Nov 17 – Dec 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 25) and first fall frost (Dec 1) 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 97232 came on Feb 7 — 11 days earlier than the 1991–2020 average (Feb 18).

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).

Soil in Portland, OR

The center of ZIP 97232 is mapped as Urban land, 3 to 15 percent slopes: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

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 97232; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Portland, OR

Summer high81 °Faverage high, August
Winter low37 °Faverage low, January
Hot days11days a year at 90 °F or more
Freezing nights18nights a year at 32 °F or less
Growing degree days2,697base 50 °F — the season’s usable heat
Longest day15 h 41 mindaylight on June 21
Shortest day8 h 42 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation44.9 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°32 °FJanuary: average high 47 °F, low 37 °F 47°37° JanFebruary: average high 51 °F, low 39 °F 51°39° FebMarch: average high 56 °F, low 41 °F 56°41° MarApril: average high 61 °F, low 44 °F 61°44° AprMay: average high 68 °F, low 49 °F 68°49° MayJune: average high 73 °F, low 53 °F 73°53° JunJuly: average high 80 °F, low 58 °F 80°58° JulAugust: average high 81 °F, low 59 °F 81°59° AugSeptember: average high 75 °F, low 55 °F 75°55° SepOctober: average high 63 °F, low 48 °F 63°48° OctNovember: average high 52 °F, low 42 °F 52°42° NovDecember: average high 46 °F, low 37 °F 46°37° Dec

Precipitation by month inches

0″2″4″6″8″January: 6.50 in precipitation 6.5 JanFebruary: 4.39 in precipitation 4.4 FebMarch: 4.90 in precipitation 4.9 MarApril: 3.71 in precipitation 3.7 AprMay: 3.01 in precipitation 3.0 MayJune: 1.72 in precipitation 1.7 JunJuly: 0.55 in precipitation 0.6 JulAugust: 0.57 in precipitation 0.6 AugSeptember: 1.62 in precipitation 1.6 SepOctober: 3.87 in precipitation 3.9 OctNovember: 6.74 in precipitation 6.7 NovDecember: 7.28 in precipitation 7.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Portland Kgw-Tv, OR (2 mi away); precipitation: Portland 0.8 Ene, OR (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

972149a
Portland, OR · 1 mi
972128b
Portland, OR · 1 mi
972079a
Portland, OR · 2 mi
972289a
Portland, OR · 2 mi
972389a
Portland, OR · 2 mi
972409a
Portland, OR · 2 mi
972429a
Portland, OR · 2 mi
972509a
Portland, OR · 2 mi

All 59 ZIP codes in Portland → · Oregon planting zones →

Questions about 97232

What planting zone is ZIP code 97232?

ZIP code 97232 (Portland, OR) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in Portland, OR?

The median last spring frost (32 °F) near 97232 is February 25; after March 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Portland Kgw-Tv station.

When is the first frost in Portland, OR?

The median first fall frost near 97232 is December 1, giving a median frost-free growing season of 280 days.

When should I plant tomatoes in 97232?

Start tomato seeds indoors around Dec 31 – Jan 14 and set transplants outside around Mar 4 – Mar 18, one to three weeks after the median last frost.

How much rain and snow does 97232 get?

About 44.9 inches of precipitation a year (NOAA 1991–2020 normals, Portland 0.8 Ene station).

How hot do summers get in Portland, OR?

The average high peaks at 81 °F in August, with about 11 days a year at 90 °F or more.

Did spring come early in Portland, OR in 2026?

Spring leaf-out near 97232 came on Feb 7 in 2026, 11 days earlier than the 1991–2020 average (Feb 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Portland, OR?

Long-day onions: the longest day near 97232 is 15 h 41 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 97232 change?

Yes. The 2012 USDA map put 97232 in zone 8b; the 2023 map puts it in zone 9a. The newer map uses 1991–2020 data and more weather stations.