Rainline Garden

When to plant cauliflower in Wilsonville and Canby, OR

Start cauliflower from seed indoors Jan 25 – Feb 8, then plant the young plants in the garden in Wilsonville and Canby Mar 15 – Apr 12. For a fall harvest, plant again Jul 16–30.

Tricky here Plant young plants (starts)

Why these dates

Wilsonville and Canby's typical last spring frost is March 16. As a cool-season crop that handles light frost, this crop doesn't need to wait for that date. In the west-side valleys, though, the soil usually isn't ready to work until about March 15.

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
Tricky here
Sun
Full sun
Spacing
18 to 24 inches apart
Planting depth
Plant starts at the depth they grew in the pot
Frost
Handles light frost
First harvest
About 75 days after planting

Step by step

  1. Start seeds indoors Jan 25 – Feb 8 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 Mar 15 – Apr 12, 18 to 24 inches apart. Plant starts at the depth they grew in the pot.
  4. Water deeply once or twice a week rather than a little every day, and mulch once the soil is warm.
  5. Plant again Jul 16–30 for a fall harvest.
  6. Harvest: Cut the head while it's firm and tight, before the curds start to separate. Tie the outer leaves over young heads to keep them white.

Varieties that do well here

  • Snow Crown
  • Amazing
  • Graffiti (purple)

Watch out for

A cold snap or dry spell makes plants form tiny 'button' heads. Keep the soil evenly moist and don't rush spring planting.

Fussier than broccoli: a setback from a cold snap or dry soil makes tiny 'button' heads. Fall crops are often the most reliable here.

Common questions

When is the last frost in Wilsonville and Canby, OR?

Typically March 16. In 9 years out of 10, frost is over by April 7. These are 1991–2020 NOAA climate normals for Aurora State Airport.

Is it too late to plant cauliflower in Wilsonville and Canby?

The spring planting window runs through April 12. If you miss it, plant again for fall from July 16 to July 30.

When should I start cauliflower from seed indoors in Wilsonville and Canby?

January 25 to February 8, which is 7 to 5 weeks before the March 15 planting date. Or buy young plants at a garden center instead.

Also plant in Wilsonville and Canby around the same time

Planting dates for cauliflower in nearby areas

Full planting calendar for Wilsonville and Canby · Cauliflower in every city