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A white cauliflower head forming in the middle of a leafy plant
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When to plant cauliflower in John Day, OR

Start cauliflower from seed indoors Mar 12–26, then plant the young plants in the garden in John Day Apr 30 – May 28. For a fall harvest, plant again Jun 19 – Jul 3.

Tricky here Plant young plants (starts)

Difficulty
Tricky here
Sun
Full sun
Spacing
18 to 24 inches apart
Planting depth
Plant starts at the depth they grew in the pot
Frost
Handles light frost
First harvest
About 75 days after planting

Why these dates

John Day's typical last spring frost is May 28. As a cool-season crop that handles light frost, this crop can go in about 4 weeks before that.

High desert and mountains. Central and high eastern Oregon. Frost is possible almost any month. Use row covers, wall-o-water or cloches for warm crops, and choose short-season varieties.

How to grow cauliflower in John Day

  1. Start seeds indoors Mar 12–26 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 30 – May 28, 18 to 24 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 Jun 19 – Jul 3 for a fall harvest.
  6. Harvest: Cut the head while it's firm and tight, before the curds start to separate. Tie the outer leaves over young heads to keep them white.

Key numbers

Growing notes

What makes the difference in Northwest gardens, in plain language.

Soil and feeding

Cauliflower needs rich, moisture-holding soil with plenty of compost and a pH of about 6.0 to 7.0. It is sensitive to a shortage of boron, a trace nutrient, which can cause hollow stems and brown heads; a good compost or a complete vegetable fertilizer usually covers it. Side-dress with nitrogen about a month after planting. Above all, keep growth steady. Cauliflower has little tolerance for a check in growth, so water evenly and mulch once the soil is warm.

Why cauliflower makes tiny heads

If young plants are stressed by cold, drought, crowding or being root-bound, they can form a small "button" head early instead of a full one. That's why the guide warns against rushing spring planting. Set out young, healthy starts after the worst cold has passed, and don't let them dry out. In the Northwest, fall crops planted in mid-summer are often the most reliable, because heads form in cool, even weather. East of the Cascades, hot early summer weather can also cause loose, ricey heads, which is another reason fall crops shine there.

Blanching, harvest and storage

Sunlight turns white heads yellowish and stronger tasting. When the head is about the size of an egg, pull the outer leaves over it and tie them loosely, or snap a few leaves over the top. Purple types like Graffiti don't need this. Check under the leaves every few days, since heads go from ready to overripe quickly. Cut while the curds are tight and smooth. Cauliflower keeps about a week in the fridge, and blanched florets freeze well.

Common questions

When is the last frost in John Day, OR?

Typically May 28. In 9 years out of 10, frost is over by June 15. These are 1991–2020 NOAA climate normals for John Day.

Is it too late to plant cauliflower in John Day?

The spring planting window runs through May 28. If you miss it, plant again for fall from June 19 to July 3.

When should I start cauliflower from seed indoors in John Day?

March 12 to March 26, which is 7 to 5 weeks before the April 30 planting date. Or buy young plants at a garden center instead.

Why is my cauliflower head so small?

Stress early in life, from cold snaps, dry soil, or pot-bound transplants, makes plants form small button heads. Plant young starts, keep the soil evenly moist and feed well. Fall crops usually do better in the Northwest.

Why is my cauliflower turning yellow or purple?

Sun exposure discolors white heads. Tie the outer leaves over the head when it's small to keep it pale. The color change is harmless, though the flavor gets a bit stronger.

When should I plant fall cauliflower?

Set out starts in mid-summer so heads form in the cool weather of fall. Keep young plants well watered through late summer heat. Check the planting calendar for your area's dates.

Also plant in John Day around the same time

Planting dates for cauliflower in nearby areas

Full planting calendar for John Day · Cauliflower in every city