Cool-Season Vegetable

When to Plant Cauliflower in Oregon

The diva of the brassica family. More temperamental than broccoli but worth the extra attention.

The Short Answer

Cauliflower are cold-tolerant and do well in Oregon's mild climate. Oregon gardeners can also plant a fall crop. Rich volcanic soils in Willamette Valley. Dry, alkaline soils east of Cascades. Acidic forest soils...

Oregon Frost Dates

Your planting dates depend on which part of Oregon you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Willamette Valley 8a, 8b Mar 25 - Apr 15 Oct 15 - Nov 10
Portland Metro 8b, 9a Mar 15 - Apr 5 Oct 25 - Nov 15
Central/Eastern Oregon 5a, 5b, 6a, 6b May 10 - Jun 1 Sep 10 - Oct 1
Southern Oregon Coast 8b, 9a, 9b Mar 5 - Mar 25 Nov 5 - Nov 25

Cauliflower Planting Schedule for Oregon

Willamette Valley (Zones 8a, 8b)

Average last frost: Mar 25 - Apr 15 · Average first frost: Oct 15 - Nov 10

Start Seeds Indoors
6 wks before frost
Transplant Outside
2 wks before frost
Fall Planting
10 wks before first frost

Portland Metro (Zones 8b, 9a)

Average last frost: Mar 15 - Apr 5 · Average first frost: Oct 25 - Nov 15

Start Seeds Indoors
6 wks before frost
Transplant Outside
2 wks before frost
Fall Planting
10 wks before first frost

Central/Eastern Oregon (Zones 5a, 5b, 6a, 6b)

Average last frost: May 10 - Jun 1 · Average first frost: Sep 10 - Oct 1

Start Seeds Indoors
6 wks before frost
Transplant Outside
2 wks before frost
Fall Planting
10 wks before first frost

Southern Oregon Coast (Zones 8b, 9a, 9b)

Average last frost: Mar 5 - Mar 25 · Average first frost: Nov 5 - Nov 25

Start Seeds Indoors
6 wks before frost
Transplant Outside
2 wks before frost
Fall Planting
10 wks before first frost

Growing Cauliflower in Oregon

Cauliflower in Oregon's Climate

Cauliflower requires the most precise timing of any brassica in warm climates. Your 'cool season' may be warmer than northern states' summers, making heading unpredictable. Choose heat-tolerant varieties bred to head at warmer temperatures. Fall planting targeting head development in December-January is most reliable.

Soil Considerations for Oregon

Rich volcanic soils in Willamette Valley. Dry, alkaline soils east of Cascades. Acidic forest soils on coast. Generally excellent for gardening in valleys.

Oregon Climate & Growing Season

Dramatic east-west climate divide. Wet, mild winters west of Cascades. Dry, cold winters east. Year-round gardening possible in mild western valleys.

Growing season length varies across Oregon: Willamette Valley (8a, 8b) has a last frost around Mar 25 - Apr 15, while Southern Oregon Coast (8b, 9a, 9b) sees frost end around Mar 5 - Mar 25. This difference matters for cauliflower — adjust your planting dates to match your specific region.

Growing Tips

Blanch white varieties by tying outer leaves over the head when it reaches 2 inches. Temperature swings cause buttoning.

Companion Planting

Plant cauliflower alongside these companions for better growth:

Beets Celery Onions

Keep cauliflower away from:

Strawberries Tomatoes

The Bottom Line

Cauliflower can be grown successfully across Oregon, but your exact planting dates depend on which region you're in. Willamette Valley gardeners should plan around a Mar 25 - Apr 15 last frost, while those in Southern Oregon Coast can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Cauliflower Growing Guide National planting guide with all states Oregon Planting Calendar All plants for Oregon Cauliflower in Alabama Alabama planting dates Cauliflower in Alaska Alaska planting dates Cauliflower in Arizona Arizona planting dates Cauliflower in Arkansas Arkansas planting dates
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

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