Rainline Garden

When to plant cucumbers in Portland, OR

Plant cucumbers in the garden in Portland May 10 – Jun 7, either as seeds or as young plants started indoors Apr 12–19.

Moderate Plant seeds or young plants

Why these dates

Portland's typical last spring frost is March 13. Frost kills cucumbers, and warm-season crops also need warm soil. Soil here stays cold for weeks after the last frost, so planting waits until about May 10.

West-side valleys. The Willamette Valley, Puget Sound and southern Oregon valleys. Long frost-free seasons, but soil stays cold and wet into May, so warm crops wait for warm soil, not just the last frost.

Difficulty
Moderate
Sun
Full sun
Spacing
12 inches apart on a trellis
Planting depth
1 inch deep
Frost
Killed by frost
First harvest
About 60 days after planting

Step by step

  1. Start seeds indoors Apr 12–19 in trays or small pots under a grow light or in your sunniest window. Or skip this step and buy young plants (starts) at a garden center.
  2. Harden off the young plants: about a week before planting, set them outside for a few hours a day, a little longer each day.
  3. Plant them in the garden May 10 – Jun 7, 12 inches apart on a trellis. If you plant seeds instead, sow them 1 inch deep.
  4. Water deeply once or twice a week rather than a little every day, and mulch once the soil is warm.
  5. Harvest: Pick slicers at 6 to 8 inches, before they yellow. Check plants every day or two in midsummer.

Varieties that do well here

  • Marketmore 76
  • Lemon
  • Diva

Watch out for

Powdery mildew in late summer. Grow them up a trellis for airflow and water at the base.

Need warm soil and warm nights. Floating row cover helps in cool springs.

Common questions

When is the last frost in Portland, OR?

Typically March 13. In 9 years out of 10, frost is over by April 1. These are 1991–2020 NOAA climate normals for Portland International Airport.

Is it too late to plant cucumbers in Portland?

The spring planting window runs through June 7. Later plantings may not have time to produce before the first fall frost, which usually arrives around November 19.

When should I start cucumbers from seed indoors in Portland?

April 12 to April 19, which is 4 to 3 weeks before the May 10 planting date. Or buy young plants at a garden center instead.

Also plant in Portland around the same time

Planting dates for cucumbers in nearby areas

Full planting calendar for Portland · Cucumbers in every city