Rainline Garden

When to plant broccoli in Walla Walla, WA

Start broccoli from seed indoors Feb 11–25, then plant the young plants in the garden in Walla Walla Apr 1 – May 6. For a fall harvest, plant again Jul 23 – Aug 6.

Moderate Plant young plants (starts)

Why these dates

Walla Walla's typical last spring frost is March 27. In the Columbia Basin and low eastern valleys, the soil is usually ready for broccoli around April 1.

Columbia Basin and low eastern valleys. Hot, dry summers and quick spring warm-up. Warm crops go in earlier than west of the Cascades, and irrigation matters more than rain.

Difficulty
Moderate
Sun
Full sun
Spacing
18 inches apart
Planting depth
Plant starts at the depth they grew in the pot
Frost
Handles light frost
First harvest
About 70 days after planting

Step by step

  1. Start seeds indoors Feb 11–25 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 Apr 1 – May 6, 18 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 23 – Aug 6 for a fall harvest.
  6. Harvest: Cut the main head while the buds are tight and dark green. Side shoots follow for weeks.

Varieties that do well here

  • Packman
  • Green Magic
  • Purple Sprouting (overwinters west of the Cascades)

Watch out for

Cabbage worms and aphids. Cover young plants with insect netting.

Harvest the main head while buds are tight; side shoots follow for weeks.

Common questions

When is the last frost in Walla Walla, WA?

Typically March 27. In 9 years out of 10, frost is over by April 22. These are 1991–2020 NOAA climate normals for Walla Walla Regional Airport.

Is it too late to plant broccoli in Walla Walla?

The spring planting window runs through May 6. If you miss it, plant again for fall from July 23 to August 6.

When should I start broccoli from seed indoors in Walla Walla?

February 11 to February 25, which is 7 to 5 weeks before the April 1 planting date. Or buy young plants at a garden center instead.

Also plant in Walla Walla around the same time

Planting dates for broccoli in nearby areas

Full planting calendar for Walla Walla · Broccoli in every city