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Fresh green asparagus spears close up
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When to plant asparagus in Kent, Renton and Auburn, WA

Plant asparagus crowns in Kent, Renton and Auburn Mar 15 – Apr 26.

Moderate Plant dormant crowns

Why these dates

Kent, Renton and Auburn's typical last spring frost is March 20. As a hardy perennial, 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
Moderate
Sun
Full sun
Spacing
12 to 18 inches apart
Planting depth
In a trench 6 to 8 inches deep, covered gradually as the spears grow
Frost
Hardy perennial; comes back every year
First harvest
Light picking in year two; full harvests from year three

Step by step

  1. Pick a sunny spot with soil that drains well, and mix in an inch or two of compost.
  2. Plant asparagus crowns Mar 15 – Apr 26, 12 to 18 inches apart. In a trench 6 to 8 inches deep, covered gradually as the spears grow.
  3. Fill the trench in gradually as the shoots grow. Keep the bed weeded, and cut the ferns down only after they turn brown in fall.
  4. Harvest: Snap spears at soil level when they're 6 to 8 inches tall. Stop picking when new spears are pencil-thin, and let the ferns grow.

Varieties that do well here

  • Jersey Knight
  • Millennium
  • Purple Passion

Watch out for

Asparagus beetles chew the spears and ferns. Hand-pick them in the morning.

A bed that produces for 15 to 20 years. Don't harvest the first year, pick lightly the second, then fully from year three.

Common questions

When is the last frost in Kent, Renton and Auburn, WA?

Typically March 20. In 9 years out of 10, frost is over by April 8. These are 1991–2020 NOAA climate normals for Kent.

Is it too late to plant asparagus in Kent, Renton and Auburn?

The spring planting window runs through April 26. Potted plants can still go in later if you water them faithfully through their first summer. Fall planting also works well here.

How long until I can pick asparagus?

Light picking in year two; full harvests from year three. Snap spears at soil level when they're 6 to 8 inches tall. Stop picking when new spears are pencil-thin, and let the ferns grow.

Also plant in Kent, Renton and Auburn around the same time

Planting dates for asparagus in nearby areas

Full planting calendar for Kent, Renton and Auburn · Asparagus in every city