Annual Flower

When to Plant Sunflowers in California

Few things bring more joy than a row of sunflowers turning their faces to the sun. Easy, dramatic, and pollinator-friendly.

The Short Answer

California's intense sun grows spectacular sunflowers — the crop thrives in the same conditions that make the state an agricultural powerhouse. Inland gardens produce the tallest, most robust plants.

California Frost Dates

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

Region Zones Last Frost (Spring) First Frost (Fall)
Northern California Mountains 5a, 5b, 6a, 6b May 1 - May 25 Sep 20 - Oct 15
Central Valley 9a, 9b Feb 10 - Mar 1 Nov 15 - Dec 5
Southern California Coast 10a, 10b, 11a Jan 1 - Feb 1 Dec 10 - Jan 1
Bay Area 9b, 10a Jan 20 - Feb 15 Nov 25 - Dec 15

Sunflowers Planting Schedule for California

Northern California Mountains (Zones 5a, 5b, 6a, 6b)

Average last frost: May 1 - May 25 · Average first frost: Sep 20 - Oct 15

Start Seeds Indoors
2 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Central Valley (Zones 9a, 9b)

Average last frost: Feb 10 - Mar 1 · Average first frost: Nov 15 - Dec 5

Start Seeds Indoors
2 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Southern California Coast (Zones 10a, 10b, 11a)

Average last frost: Jan 1 - Feb 1 · Average first frost: Dec 10 - Jan 1

Start Seeds Indoors
2 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Bay Area (Zones 9b, 10a)

Average last frost: Jan 20 - Feb 15 · Average first frost: Nov 25 - Dec 15

Start Seeds Indoors
2 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Growing Sunflowers in California

State-Specific Growing Tips

Central Valley: sow March through June. Bay Area: sow April through June. Southern California: sow March through July. Mountain: sow May through June. California's dry climate means minimal disease. Direct sow in full sun. Drip irrigation during establishment, then reduce.

Recommended Varieties for California

Everything thrives in California's warm, sunny conditions. Mammoth, ProCut, Sunrich, Teddy Bear (dwarf). Multi-stem varieties for cut flowers.

Common Challenges in California

Birds eat seeds. Spider mites in hot, dry inland areas. Gophers eat roots. Minimal disease.

Growing Tips

Direct sow is preferred — sunflowers don't love transplanting. Succession plant every 2 weeks for blooms all summer.

Companion Planting

Plant sunflowers alongside these companions for better growth:

Cucumbers Squash Corn

Keep sunflowers away from:

Potatoes

The Bottom Line

Sunflowers can be grown successfully in California with proper attention to regional frost dates and local growing conditions. Timing varies across the state — Northern California Mountains gardeners work with a last frost around May 1 - May 25, while Bay Area sees frost end around Jan 20 - Feb 15. Choose varieties suited to your region, amend your soil based on its specific needs, and monitor for the pests and diseases most common in your area. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Sunflowers Growing Guide National planting guide with all states California Planting Calendar All plants for California Sunflowers in Alabama Alabama planting dates Sunflowers in Alaska Alaska planting dates Sunflowers in Arizona Arizona planting dates Sunflowers 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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