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Kohlrabi bulbs swelling above the soil in a garden row
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When to plant kohlrabi in Pullman, WA

Plant kohlrabi in the garden in Pullman Apr 15 – May 27, either as seeds or as young plants started indoors Mar 4–18. For a fall harvest, plant again Jul 31 – Aug 14.

Easy Plant seeds or young plants

Why these dates

Pullman's typical last spring frost is April 29. As a cool-season crop that handles light frost, this crop doesn't need to wait for that date. In the Inland Northwest, though, the soil usually isn't ready to work until about April 15.

Inland Northwest. Higher, colder interior valleys. Cold springs and an earlier fall mean a shorter season; quick-maturing varieties pay off.

Difficulty
Easy
Sun
Full sun
Spacing
Thin to 6 inches apart
Planting depth
¼ to ½ inch deep
Frost
Handles light frost
First harvest
About 55 days after planting

Step by step

  1. Start seeds indoors Mar 4–18 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 15 – May 27, Thin to 6 inches apart. If you plant seeds instead, sow them ¼ to ½ inch deep.
  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 31 – Aug 14 for a fall harvest.
  6. Harvest: Cut bulbs at 2 to 3 inches across. Peel off the tough skin and eat raw or cooked.

Varieties that do well here

  • Kolibri (purple)
  • Winner
  • Kossak (large, stores well)

Watch out for

Cabbage worms chew the leaves. Insect netting keeps the white moths from laying eggs.

Pick when the bulb is about tennis-ball size; bigger ones turn woody.

Common questions

When is the last frost in Pullman, WA?

Typically April 29. In 9 years out of 10, frost is over by May 14. These are 1991–2020 NOAA climate normals for Pullman-Moscow Regional Airport.

Is it too late to plant kohlrabi in Pullman?

The spring planting window runs through May 27. If you miss it, plant again for fall from July 31 to August 14.

When should I start kohlrabi from seed indoors in Pullman?

March 4 to March 18, which is 6 to 4 weeks before the April 15 planting date. Or buy young plants at a garden center instead.

Also plant in Pullman around the same time

Planting dates for kohlrabi in nearby areas

Full planting calendar for Pullman · Kohlrabi in every city