When to plant peppers in Portland, Oregon

March 11 – March 25

Transplant outdoors · typical Portland year

Climate basis: NOAA station Portland Kgw-tv, OR (USC00356749), 1 mi (1 km) from downtown Portland (ZCTA 97204 centroid), elevation 159 ft, on the 1991–2020 climate normals. Transplant peppers outdoors from approximately the dates above, anchored to the median last spring 32°F freeze (February 25). One year in ten still freezes after March 21.

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 Portland year

Start seeds indoorsDec 31 – Jan 14
Transplant outdoorsMar 11 – Mar 25
  • indoors under lights
  • in the garden
  • frost-free season
  • 1-in-10 years still freeze to Mar 21
Peppers in Portland · freeze context from Portland Kgw-tv, OR, 1991–2020 normals.

Every method, with its sources

Start seeds indoors

Dec 31 – Jan 14

Sow 8–10 weeks before the transplant window opens (UNH 8–10 weeks; Missouri G6570 8–10 weeks in pots). Anchored to the median last spring freeze (Feb 25). University of New Hampshire Extension · University of Missouri Extension

Transplant outdoors

Mar 11 – Mar 25

UNH: set out 2 weeks after last frost. Purdue: very tender — plant at least two weeks after the average last frost. Point rule given a 14-day span. Anchored to the median last spring freeze (Feb 25). University of New Hampshire Extension · Purdue University Extension

Variety assumption: Assumes an average bell/chile variety (roughly 65–80 days from transplant).

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.

This week, not a typical year:
Crop rule sources (3)

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