Brassica oleracea (Italica Group)

The Italica Group is commonly called broccoli.  The Genus name Brassica is Latin for cabbage.  It is a cool-season vegetable that is typically grown in the spring or fall and is harvested to eat the stems and unopened flower buds.  While less commonly eaten, the leaves and opened flowers are edible as well.  This cultivar group is in the same species as some other well-known cruciferous vegetables such as cauliflower, cabbage, and Brussels Sprouts, set apart by selective breeding for thick stems and large, compact flower heads.

Broccoli grows best in full sun and moist, rich, well-drained soil.  They prefer loamy soil at a pH of around 6-7.  Consistent, steady moisture is needed throughout the growing season as water stress leads to bitter flavors and stunted growth.  As they also need consistent nutrition, additional compost or fertilizer may be added around the plant once it is about 4 in tall.  Daytime temperatures above 80 degrees will affect the plant, causing poor growth.  Applying mulch around these plants will ensure that the shallow roots remain protected and moist as well as provide a form of weed control.

In NC, it is recommended to grow broccoli via transplants– especially if growing a spring crop– as our summers are long and hot.  Start transplants indoors 6-8 weeks before planting.  For spring, plant transplants between mid-February and April; for fall, plant between mid-July and mid-September.  Plants can be spaced anywhere from 6-18 in apart.

Harvest as soon after the heads become firm and tight; prior to the buds opening is best as the heads quickly lose quality once they bloom.  In NC, spring harvest will be around mid-May through June and fall around mid-October through November.  Once the center head is removed, the plant will continue to produce smaller offshoots that can also be harvested.  Although broccoli can be eaten raw, it is typically served boiled or steamed.  Outer leaves can be harvested sparingly before the flower buds form and more intensely by the end of the season; use similarly to collard greens.  If the plant does flower before harvest, flowers and young seed pods can be eaten raw in salads or as a garnish.

Insects, Pests and other Plant Problems:  Cabbageworms, cabbage loopers, aphids, caterpillars and slugs are insects that may cause problems for broccoli.  Leaf spot, blackleg, and black rot are health issues.

The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common Cole crop diseases and other plant problems.

VIDEO Created by Elisabeth Meyer for "Edibles, Bulbs, and Houseplants" a plant identification course offered in partnership with Longwood Gardens.   

More information on Brassica oleracea.