Portland, Oregon: freeze dates & growing season

Three different things get called “Portland” here, so this page is explicit about all three: the metro label (Portland), the anchor geography (Census ZCTA 97204, a downtown ZIP-code area), and the climate record (the NOAA station below). Windows are calculated from the station — not from your street address.

Climate basis: NOAA station Portland Kgw-tv, OR (USC00356749), 1 mi (1 km) from the ZCTA 97204 centroid, elevation 159 ft, on the 1991–2020 climate normals.
Last spring freezeFebruary 251-in-10 after Mar 21
First fall freezeDecember 11-in-10 before Nov 10
Frost-free season280 daysmedian at 32°F
Hard freeze, 28°Jan 31Dec 20kills even hardy greens
USDA zone9a20 to 25°F winter low not frost timing

The year

  • indoors under lights
  • in the garden
  • frost-free season
  • 1-in-10 years still freeze to Mar 21
The Portland year: hatched areas are the freeze-likely seasons in 1991–2020 normals.
What that means in practice
All 79 crops in Portland

These windows describe typical years (1991–2020 climate normals), not this year's forecast. Freezes happen outside them — especially in frost pockets, valleys, and urban edges. Watch the forecast before committing tender plants.

Check a specific ZIP instead

Metro climates vary — elevation, water, and urban heat shift freeze dates by days to weeks. Look up your exact ZIP:

Nearby reviewed metros

Seattle, WA · Spokane, WA · Boise, ID · Reno, NV · Sacramento, CA