Broccoli Growing Guide: Tips for Planting, Care, and Harvesting
Broccoli is a popular cool-weather vegetable that offers a delicious and nutritious harvest. Whether you are planting a spring or fall crop, understanding broccoli varieties, proper planting techniques, and pest management will help you enjoy a productive garden.
Click here to access the complete Broccoli Growing Guide (PDF) for detailed information on soil preparation, planting, and long-term care.
Types of Broccoli
• Calabrese: Short-season Italian variety with thick stems and dark green heads. Produces one large head and many side shoots.
• Raab: Italian heirloom known for tender flower shoots and strap-leaves. Best for cool weather but not suitable for cold winters.
• Romanesco: Hybrid between broccoli and cauliflower with spiral heads and a nutty flavor. Long-season variety.
• Purple Sprouting: Cold-hardy to below 10°F, producing sweet purple heads in spring. Suitable for fall planting.
• Chinese (Chinese Kale): Grown for its succulent stalks and flavorful leaves. Slightly bitter, best harvested when buds are closed.
Best Growing Conditions for Broccoli
Soil and Temperature:
• pH: 6.0–7.0
• Preferred Temperature: 60–65°F (Tolerates 40–75°F)
• Seed Longevity: About 3 years when stored properly.
Planting and Spacing:
• Spacing: Sow seeds 4–6 inches apart, thin to 12–24 inches, with rows 18–36 inches apart.
• Companion Plants: Beets, spinach, chard, garlic, potatoes, cucumbers, rosemary.
• Incompatible Plants: Cabbage, cauliflower, eggplant, beans, tomatoes, strawberries.
Watering and Fertilizing Broccoli
• Watering: Use drip or furrow irrigation to water deeply at soil level and prevent stunted growth. Maintain consistent moisture using mulch.
• Fertilization: Broccoli is a heavy feeder. Apply side dressings of nitrogen (e.g., feather meal or blood meal) every 4 weeks, tapering off after heads form. Use nitrogen-fixing cover crops like PV Soil Builder Mix or Nitro-Max Plow Down Mix in crop rotations.
How to Plant and Grow Broccoli
Spring Planting:
• Start Indoors: 6–8 weeks before the last frost.
• Transplant Outdoors: 2–3 weeks before the last spring frost. Use Agribon AG15 row covers for protection.
• Mulch: To suppress weeds and retain moisture.
Fall Planting:
• Direct Sow: Between July and August, or 85–100 days before the first fall frost.
• Best for Mild Winter Climates: Purple sprouting broccoli is ideal for late summer to fall planting as it thrives in cool weather and overwinters well.
• Watering: Maintain consistent moisture and mulch for temperature regulation.
Harvesting Broccoli
• When to Harvest: Cut heads while they are still tight, before they split or bolt. Use a sharp knife to cut at an angle, leaving 6 inches of stem attached.
• Side Shoots: After harvesting the main head (except Romanesco), continue harvesting side shoots for extended production.
• Purple Sprouting: Ideal for early spring harvest after overwintering.
Common Broccoli Pests and Diseases
Pests:
• Aphids: Found on leaf undersides or flower heads. Control with strong water sprays, beneficial insects (like ladybugs), or organic insecticides.
• Lepidopteran Pests: Includes cabbage loopers, armyworms, and cabbage worms. Hand-pick, use beneficial insects, or organic insecticides.
• Flea Beetles: Cause tiny holes in leaves. Use sticky traps, row covers, or organic insecticides.
• Harlequin Bugs: Create white spots on leaves. Hand-pick or use row covers and organic insecticides.
• Swede Midge: Prevent with row covers and organic insecticides.
Diseases:
• Downy Mildew: Caused by poor air circulation and wet leaves. Use drip irrigation, keep foliage dry, and apply organic fungicides.
Integrated Pest Management (IPM) for Broccoli
• Cultural Controls: Remove plants promptly after harvest to eliminate insect habitats.
• Clean Transplants: Use only disease-free seedlings.
• Crop Rotation: Rotate cole crops every 3 years to prevent pest buildup.
• Row Covers: Use Agribon AG15 covers before insects arrive.
Why Grow Broccoli?
• Nutrient-Rich: High in vitamins C and K, fiber, and antioxidants.
• Multiple Harvests: Continuous side shoots after harvesting the central head.
• Cold-Hardy: Perfect for spring and fall planting.
• Diverse Varieties: Wide selection from Calabrese to Romanesco.