Broccoli is a hardy vegetable of the cabbage family that is high in vitamins A and D. It develops best during cool seasons of the year. When broccoli plants of most varieties are properly grown and harvested, they can yield over an extended period. Side heads develop after the large, central head is removed. Two crops per year (spring and fall) may be grown in most parts of the country. New heat tolerant varieties allow broccoli to be produced in all but the hottest parts of the season. Transplants are recommended to give the best start for spring planting, because transplanting gets the plants establish more quickly. Thus they can bear their crop with minimal interference from the extreme heat of early summer. Fall crops may be direct-seeded in the garden if space allows or may be started in flats to replace early crops when their harvest ends. Use starter fertilizer for transplants and side-dress with nitrogen fertilizer when the plants are half grown. Provide ample soil moisture, especially as the heads develop.
Transplant young, vigorously growing plants in early spring.
The edible part of broccoli are compact clusters of unopened flower buds and the attached portion of stem. The green buds develop first in one large central head and later in several smaller side shoots. Cut the central head with 5 to 6 inches of stem.
Plant seeds 1/4 to 1/2 inch deep, or set transplants slightly deeper than they were grown originally. Plant or thin seedlings 18 to 24 inches apart in the row and allow 36 inches between rows. Broccoli plants grow upright, often reaching a height of 2 1/2
Additional pests and problems that may affect this plant:
- Imported cabbage worm
- Cabbage looper
- Alternaria black spot (Alternaria brassicae and A. brassicicola)
- Bacterial soft rot (Erwinia carotovora)
- Black leg (Phoma lingam)
- Black rot (Xanthomonas campestris pv. campestris)
- Club root (Plasmodiophora brassicae)
- Fusarium yellows (Fusarium oxysporum f.sp. conglutinans)
- Rhizoctonia bottom rot (Rhizoctonia solani)
- Sclerotinia stem rot (Sclerotinia sclerotiurum)
- Wirestem (Rhizoctonia solani)
Adapted to light, heavy or muck soils. Require adequate supply of moisture. Cool season vegetable, does not perform well under hot conditions.