When to plant arugula in Walla Walla, WA

Plant arugula from seed, directly in the garden in Walla Walla, Mar 20 – May 1. For a fall harvest, plant again Aug 27 – Sep 17.

Easy Plant seeds in the ground

Why these dates

Walla Walla's typical last spring frost is March 27. As a cool-season crop that handles light frost, this crop doesn't need to wait for that date. In the Columbia Basin and low eastern valleys, though, the soil usually isn't ready to work until about March 20.

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: Easy
Sun: Full sun to part shade
Spacing: Thin to 4 inches apart
Planting depth: ¼ inch deep
Frost: Handles light frost
First harvest: About 35 days after planting

Step by step

Prepare the bed: loosen the soil and mix in an inch or two of compost.
Plant seeds Mar 20 – May 1, ¼ inch deep, Thin to 4 inches apart.
Keep the soil evenly moist until sprouts appear, which can take one to three weeks in cool soil.
Plant again Aug 27 – Sep 17 for a fall harvest.
Harvest: Pick leaves when they're 2 to 3 inches long, about three weeks after sowing. Young leaves are the mildest.

Varieties that do well here

Astro
Wild arugula (Sylvetta)
Rocket

Watch out for

Flea beetles riddle the leaves with tiny holes in spring. Floating row cover laid on at sowing keeps them off.

Fast and frost-tolerant. It bolts in heat, so sow small batches in spring and again in late summer.

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 arugula in Walla Walla?

The spring planting window runs through May 1. If you miss it, plant again for fall from August 27 to September 17.

How long until I can harvest arugula?

About 35 days after planting. Pick leaves when they're 2 to 3 inches long, about three weeks after sowing. Young leaves are the mildest.

Also plant in Walla Walla around the same time

Planting dates for arugula in nearby areas

Pendleton, OR Mar 20 – May 1
The Dalles, OR Mar 20 – May 1
Yakima, WA Mar 27 – May 8
Wenatchee, WA Mar 20 – May 1
Tri-Cities (Pasco, Kennewick, Richland), WA Mar 20 – May 1
Moses Lake, WA Mar 20 – May 1

Full planting calendar for Walla Walla · Arugula in every city