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USDA hardiness zones — 2023 map

Oregon hardiness zones — USDA planting zone map + what to grow

Zones 4b-9b · most of Oregon is zone 8b · Pacific region

OregonUSDA zone range & map

On the 2023 USDA Plant Hardiness Zone Map, Oregon spans zones 4b-9b. The map shades the state from the high desert and Cascades east of the mountains (zone 4b) through to the Willamette Valley and southwest interior (zone 9b). The single most common half-zone across the populated state is zone 8b — that is the figure to use if you only remember one number for Oregon. Oregon is split by the Cascades: a mild, wet, long-season west and a cold, dry, short-season high desert east.

USDA zone rangeZones 4b-9b
Most common zoneZone 8b
Coldest areathe high desert and Cascades east of the mountains (zone 4b)
Warmest areathe Willamette Valley and southwest interior (zone 9b)
Average last spring frostmid-April (Willamette Valley)
Average first fall frostearly November (Willamette Valley)

Source: USDA 2023 Plant Hardiness Zone Map (1991-2020 normals). Frost averages: NOAA/NCEI 1991-2020 climate normals. Local ZIP-level zones and frost dates can differ from these statewide figures.

Oregon hardiness zones by major city

Zones shift across Oregon with elevation and distance from the coast. Here is the 2023 USDA half-zone for the largest cities:

CityUSDA zone
PortlandZone 9a
EugeneZone 8b
SalemZone 8b
BendZone 6b
MedfordZone 8a

Need your exact zone? Run the ZIP-code zone finder for a precise half-zone and frost dates for your address.

ZIP-code zones in Oregon

Statewide ranges hide a lot. Tap your area for its exact USDA half-zone, last and first frost dates, and what to plant now:

What Oregon's zone range means for planting

Your hardiness zone tells you which perennials, shrubs, and trees will survive a typical Oregon winter, and it anchors when tender crops can go outside. Because Oregon spans 4b-9b, two gardeners in the same state can have very different planting calendars.

Find your exact zone in Oregon

The 4b-9b range is statewide. Growli pins your hardiness zone and frost dates to your exact ZIP code and sends a push notification before any forecast frost night for your saved location.

Frequently asked questions

What hardiness zone is Oregon?

Oregon spans USDA hardiness zones 4b-9b on the 2023 USDA Plant Hardiness Zone Map. The most common zone — covering the largest share of the populated state — is zone 8b. The coldest areas are the high desert and Cascades east of the mountains (zone 4b) and the warmest are the Willamette Valley and southwest interior (zone 9b).

When is the last frost in Oregon?

Across most of Oregon the average last spring frost falls around mid-April (Willamette Valley) and the first fall frost around early November (Willamette Valley). These are statewide averages — colder, higher areas run later in spring and earlier in fall, so check a ZIP-level estimate for your exact spot.

What grows well in Oregon?

Oregon is split by the Cascades: a mild, wet, long-season west and a cold, dry, short-season high desert east. Match plants to your local half-zone within the 4b-9b range: choose varieties hardy to at least zone 8b for reliable overwintering, and time tender crops around your local frost dates. The zone 8 planting guide lists vegetables, fruit, and ornamentals suited to most of the state.

Why does Oregon have more than one hardiness zone?

Hardiness zones track the average annual coldest temperature, which changes with latitude, elevation, distance from water, and urban heat. That is why Oregon ranges from the high desert and Cascades east of the mountains (zone 4b) to the Willamette Valley and southwest interior (zone 9b) — a span of 4b-9b — even though it is a single state.

Did Oregon's hardiness zone change in 2023?

The USDA updated the Plant Hardiness Zone Map in November 2023 using 1991-2020 climate data. About half the country, including parts of Oregon, shifted to the next warmer half-zone versus the 2012 map. The 4b-9b range here reflects the current 2023 map. Always confirm your address against the official USDA map for plant-survival decisions.

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