Calabrese Broccoli is an old Italian Heirloom broccoli that dates back to the 1800s. It grows to an average height of 76-91 cm, (30-36") with a spread that is 30-40 cm (12-16") wide. A deliciously old-fashioned broccoli, it boasts dark, bluish-green central heads about 12.7 cm (5") across. Tall, erect, 76-91 cm (30-36") plants give way to multiple side shoots once the central head is cut. It is an excellent choice for extended harvests for home gardeners. After cutting the main head, more side shoots develop, producing many more small to medium-sized heads throughout the summer.
Start broccoli seeds indoors 6-8 weeks before the last frost date in your area, or direct sow seeds in early spring or late summer. Select a location that receives full sun, or partial shade in hotter climates. Sow seeds 1cm (½”) deep, spaced 5-10cm (2-4”) apart. Keep soil moist and cool to promote germination. Seeds should sprout in 5-10 days. Thin seedlings to 30-45cm (12-18”) apart when they are 5-7cm (2-3”) tall. Broccoli prefers well-drained soil that is rich in organic matter. Soil pH should be between 6.0 and 7.5. Fertilize with a balanced fertilizer before planting and again 3-4 weeks after transplanting. Keep soil consistently moist throughout the growing season. Harvest the broccoli heads when they are tight and firm, before they start to yellow or open up.
Soil Conditions: Well-drained soil that is rich in organic matter. Soil pH: 6.0-7.5 Planting Depth: Sow seeds 1cm (½”) deep. Germination: 5-10 days. Height at Maturity: 60-90cm (24-36”) tall. Days to Maturity: 60-100 days. Watering: Keep soil consistently moist. Sun/Shade: Full sun to partial shade. Spacing after Thinning: Thin seedlings to 30-45cm (12-18”) apart.