A broccoli plant

Planting MethodActivityRecommended Dates
Spring PlantingIndoor Seed StartingDecember 1 – January 15
Transplant OutdoorsFebruary 1 – March 15
Direct SowingFebruary 1 – March 15
Fall PlantingIndoor Seed StartingJune 1 – July 15
Transplant OutdoorsAugust 1 – September 15
Direct SowingAugust 1 – September 15

Climate

USDA Hardiness zone map Northern California
USDA Hardiness zone map Southern California

California’s climate ranges from USDA Hardiness Zones 5a to 11a, significantly impacting planting schedules. The state experiences a wide range of temperatures and growing conditions, making precise timing essential.

Other planting guides for California:

Any questions on growing broccoli? Visit our forum to discuss: Growing Broccoli

Starting Broccoli Indoors

Example: In Los Angeles, CA (Zone 10b), start broccoli seeds indoors from early December to mid-January. This allows you to transplant seedlings outside from early February to mid-March.

  • What You’ll Need: Seed trays, high-quality potting mix, grow lights or a sunny window, and a consistent watering schedule.
  • How to Do It: Fill seed trays with potting mix, sow seeds about ¼ inch deep, keep the soil moist, and ensure they get plenty of light.

Direct Sowing in the Soil

Example: In Sacramento, CA (Zone 9b), you can sow seeds directly in the garden from early February to mid-March for a spring crop, and from early August to mid-September for a fall crop.

  • Preparing the Soil: Work the soil until it’s fine, mix in some compost, and ensure good drainage.
  • Sowing Seeds: Plant seeds ½ inch deep, spaced about 3 inches apart. Once seedlings have a few true leaves, thin them to 12-18 inches apart.

Transplanting Broccoli Seedlings

Example: For gardeners in San Francisco, CA (Zone 10a), start seeds indoors in early December and transplant them into the garden from early February to mid-March.

  • Preparing the Garden Bed: Make sure the soil is rich in organic matter and has a pH between 6.0 and 7.0.
  • Transplanting Technique: Space seedlings 18-24 inches apart in rows 24-36 inches apart. Water thoroughly after transplanting and apply mulch to retain moisture.

General Care and Maintenance

Watering and Feeding: Broccoli requires consistent moisture, especially during dry spells. Water at the base to avoid wetting the leaves, and use a balanced vegetable fertilizer as needed.

Pest and Disease Management: Be aware of pests like aphids and cabbage worms. Use floating row covers and organic pesticides if necessary. Rotate crops and remove plant debris to prevent disease.

Harvesting Broccoli: Harvest the heads when they are firm and tight, before the flowers start to open. Cut the main head with part of the stem attached, and the plant will often produce smaller side shoots for a continued harvest.

BeeJay