When to plant sunflower in California
California spans USDA zones 6b–11a, so the right time to plant sunflower shifts by weeks across the state. The window to sow seed directly outdoors runs from about December 29 in San Mateo to June 9 in Truckee — below are local dates for 497 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Los Angeles | 10b | January 2 | December 26 | January 2 – January 23 |
| San Diego | 10b | January 6 | December 21 | January 6 – January 27 |
| San Jose | 9b | January 2 | December 25 | January 2 – January 23 |
| San Francisco | 10a | December 30 | December 25 | December 30 – January 20 |
| Fresno | 9b | January 14 | December 14 | January 14 – February 4 |
| Sacramento | 9b | January 12 | December 16 | January 12 – February 2 |
| Long Beach | 10b | January 9 | January 5 | January 9 – January 30 |
| Oakland | 10a | January 7 | December 23 | January 7 – January 28 |
Sunflower in California: FAQ
When can I plant sunflower in California?
Across California, the time to direct-sow sunflower spans roughly December 29 in San Mateo to June 9 in Truckee, each following that city's local frost dates.
Does the sunflower planting date vary across California?
Yes. California publishes 497 cities with their own frost dates, so the right sunflower planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
How long does sunflower take to grow in California?
Sunflower takes about 70–100 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.
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