When to Plant Cauliflower in California
Published: April 24, 2026
California gardeners in Zone 9b enjoy an extended 50-week growing season for cauliflower. Cool-season crops like cauliflower do best in fall, winter, and early spring in California — the hot summers bolt these plants before they can be harvested. This guide gives exact dates for California based on your local frost calendar.
Cauliflower Planting Dates for California
| Start seeds indoors | December 11–18 |
| Last frost (average) | January 15 |
| Transplant outdoors | December 25–January 4 |
| Expect first harvest | February 18 – April 4 |
| Fall crop start | October 22–November 1 |
| Fall harvest | December 16 |
| First fall frost (average) | December 31 |
Dates above assume Zone 9b, the most common zone in California. Gardeners in cooler Santa Rosa (Zone 6b) plant 1–2 weeks later; warmer San Francisco (Zone 10b) can plant 1–2 weeks earlier.
⚠ Start cauliflower indoors 4–6 weeks before last frost. Transplant 2–4 weeks before last frost. Needs consistent moisture and cool temps — bolts in heat above 75°F.
Growing Cauliflower in California's Climate
California's warm Zone 9b climate makes cauliflower a fall, winter, and early spring crop rather than a summer one. The cool-season window runs roughly October through April in California — plant outside this window and the cauliflower will bolt (send up a flower stalk and turn bitter) before it produces a harvestable crop.
Succession planting stretches the cauliflower harvest window. Sow small amounts every two weeks from October through February — you will have staggered harvests rather than a single wave to process all at once. Bolt-resistant varieties extend the usable window an extra three to four weeks into warming weather.
Common cauliflower pests to watch for in California include Cabbage Worm and Cabbage Looper. The first line of defense is companion planting: Onion and Celery planted nearby discourage several of these pests by confusing host-plant identification or repelling adults before they can lay eggs. Weekly garden walks in the early morning catch problems when they're still manageable.
Cauliflower Garden Calendar for California
| Month | Task | Notes |
|---|---|---|
| January | Harden off seedlings | Set seedlings outdoors 1–2 hours daily, increasing gradually |
| February | First harvest window opens | Cauliflower begins producing 55–100 days after transplant |
| March | — | Off-season |
| April | — | Off-season |
| May ← | Watch for bolting | Harvest promptly; spring heat arrives quickly |
| June | — | Off-season |
| July | — | Off-season |
| August | — | Off-season |
| September | — | Off-season |
| October | Fall crop planting | Transplant or direct sow for fall harvest before frost |
| November | — | Off-season |
| December | Transplant outdoors | Soil temp must be 45°F+; nighttime lows above 50°F |
Cauliflower Growing Tips for California Gardeners
- •Blanch white varieties by tying outer leaves over the head when it reaches egg-size — prevents yellowing from sun exposure.
- •Keep soil evenly moist — drought stress causes small, bitter 'buttoning' heads instead of full curds.
- •California's cool-season cauliflower plants best in October, November, and December for winter and early spring harvest. Spring plantings bolt before producing a harvestable crop.
- •Plant fall crops in mid-July to mid-August for October harvest; fall cauliflower is usually larger and sweeter than spring.
Companion Planting for Cauliflower in California
In California's warm climate, planting cauliflower with Onion and Celery helps deter pests and improve soil. Avoid planting near Tomato and Strawberry, which inhibit cauliflower growth through root chemistry or shared pest pressure. See the full cauliflower companion planting guide for the complete list.
Cauliflower Planting Dates by City in California
Top cities in California — select for city-level frost dates and planting calendars.
Frequently Asked Questions
When should I plant cauliflower in California?
In California (Zone 9b), start cauliflower seeds indoors around December 11–18 and transplant outdoors around December 25–January 4 — 3 weeks before the state's average last frost of January 15.
What is the last frost date in California?
California's average last frost date is January 15 in the state's most common Zone 9b. Frost dates vary by city — higher elevations and northern counties run 1 to 3 weeks later than the state average. See the city list below for city-level frost dates.
Can I grow cauliflower year-round in California?
cauliflower is a cool-season crop in California, with spring and fall windows. Summer heat bolts the plants before they can produce a harvestable crop. Succession planting every 2–3 weeks stretches the harvest window.
What cauliflower varieties grow best in California?
For California's Zone 9b, consult a local nursery or extension office for cauliflower variety recommendations.
When do I start cauliflower seeds indoors in California?
Start cauliflower seeds indoors in California around December 11–18, which is 5 weeks before the state's average last frost of January 15. Use grow lights and keep soil temperatures at 70–75°F for fastest germination.