- Species and varieties: Broccoli (Brassica oleracea var. italica) is a member of the Brassicaceae family. Common varieties include Calabrese, Sprouting, and Romanesco. Calabrese is the most widely grown variety, known for its large green heads and thick stalks. Sprouting broccoli produces multiple smaller heads, and Romanesco is known for its unique fractal-shaped heads.
- Hybrid or heirloom: Broccoli seeds can be either hybrid or heirloom. Hybrid varieties are bred for specific traits such as disease resistance and uniformity, while heirloom varieties are open-pollinated and have been passed down through generations, often prized for their unique flavors and adaptability.
- Pruning and training: Broccoli does not require extensive pruning. However, removing yellowing leaves and spent heads can promote further growth and prevent disease. For sprouting varieties, harvesting the main head will encourage the growth of side shoots.
- Fertilization needs: Broccoli is a heavy feeder and benefits from regular fertilization. Incorporate a balanced fertilizer or compost into the soil before planting. Side-dress with a nitrogen-rich fertilizer every 3-4 weeks during the growing season to support vigorous growth and head development.
- Hardiness zones: Broccoli is suitable for USDA hardiness zones 3-10. It thrives in cooler climates and can tolerate light frosts, making it ideal for spring and fall planting in most regions.
- Climate requirements: Broccoli prefers temperatures between 65-75°F (18-24°C). It requires full sun and well-drained, fertile soil with a pH between 6.0 and 7.0. Consistent moisture is crucial for optimal growth, but the soil should not be waterlogged.