Rainline Garden

When to plant onions in Astoria, OR

Plant onion sets in Astoria Mar 25 – Apr 29.

Moderate Plant small onion bulbs (sets)

Why these dates

Astoria's typical last spring frost is March 26. As a cool-season crop that handles light frost, this crop doesn't need to wait for that date. On the coast, though, the soil usually isn't ready to work until about March 25.

Coast. Mild winters but cool, foggy summers. Frost is rarely the problem; warmth is. Pick early, cool-tolerant varieties of tomatoes and squash.

Difficulty
Moderate
Sun
Full sun
Spacing
4 inches apart
Planting depth
Sets 1 inch deep, tip just showing
Frost
Handles light frost
First harvest
About 110 days after planting

Step by step

  1. Prepare the bed: loosen the soil and mix in an inch or two of compost.
  2. Plant onion sets Mar 25 – Apr 29, 4 inches apart, sets 1 inch deep, tip just showing.
  3. Water regularly and keep the bed weeded; onions don't compete well.
  4. Harvest: When the tops flop over in late summer, pull the onions and let them dry in a shady, airy spot for two weeks.

Varieties that do well here

  • Walla Walla Sweet
  • Copra (stores well)
  • Redwing

Watch out for

Weeds outcompete onions' thin leaves. Keep the bed weeded and mulched.

Plant as soon as the soil is dry enough to work. Pick long-day varieties for the Northwest.

Common questions

When is the last frost in Astoria, OR?

Typically March 26. In 9 years out of 10, frost is over by April 18. These are 1991–2020 NOAA climate normals for Astoria Regional Airport.

Is it too late to plant onions in Astoria?

The spring planting window runs through April 29. Later plantings tend to struggle in summer heat.

How long until I can harvest onions?

About 110 days after planting. When the tops flop over in late summer, pull the onions and let them dry in a shady, airy spot for two weeks.

Also plant in Astoria around the same time

Planting dates for onions in nearby areas

Full planting calendar for Astoria · Onions in every city