Broccoli is an edible green plant in the cabbage family whose large flowering head is eaten as a vegetable.
The word broccoli comes from the Italian plural of broccolo, which means “the flowering crest of a cabbage”, and is the diminutive form of brocco, meaning “small nail” or “sprout”. Broccoli is often boiled or steamed but may be eaten raw. Broccoli is classified in the Italica cultivar group of the species Brassica oleracea. Broccoli has large flower heads, usually green in color, arranged in a tree-like structure branching out from a thick, edible stalk. The mass of flower heads is surrounded by leaves. Broccoli resembles cauliflower, which is a different cultivar group of the same species.Broccoli is a result of careful breeding of cultivated leafy cole crops in the northern Mediterranean starting in about the 6th century BC. Since the time of the Roman Empire, broccoli has been considered a uniquely valuable food among Italians. Broccoli was brought to England from Antwerp in the mid-18th century by Peter Scheemakers. Broccoli was first introduced to the United States by Southern Italian immigrants, but did not become widely known until the 1920s.
There are three commonly grown types of broccoli:
- The most familiar is Calabrese broccoli, often referred to simply as “broccoli”. It has large (10 to 20 cm) green heads and thick stalks. It is a cool season annual crop.
- Sprouting broccoli has a larger number of heads with many thin stalks.
- Purple cauliflower is a type of broccoli sold in southern Italy, Spain, and the United Kingdom. It has a head shaped like cauliflower, but consisting of tiny flower buds. It sometimes, but not always, has a purple cast to the tips of the flower buds.
Broccoli is a cool-weather crop that does poorly in hot summer weather. Broccoli grows best when exposed to an average daily temperature between 18 and 23 °C. When the cluster of flowers, also referred to as a “head” of broccoli, appear in the center of the plant, the cluster is green. Garden pruners or shears are used to cut the head about an inch from the tip. Broccoli should be harvested before the flowers on the head bloom bright yellow. While the heading broccoli variety performs poorly in hot weather, mainly due to insect infestation, the sprouting variety is more resistant, though attention must be paid to sucking insects (such as aphids), caterpillars and whiteflies. Spraying of bacillus thuringiensis can control caterpillar attacks, while a citronella vase may ward off whiteflies.
Easy to grow. Grow in seed trays, and plant out in 4-6weeks. Sow seed at a depth approximately three times the diameter of the seed. Choose a sunny position for both, protected from strong winds. Best planted at soil temperatures between 7°C and 30°C. Space plants: 35 – 50 cm apart. Ensure a well-drained soil, full of wellrotted compost & organic matter with a pH of 6.5-7.
Correct soil pH should prevent a myriad of nutrient related issues, as will a light application of chook poo based fertiliser pellets when preparing the bed. Feed both weekly with a seaweed or compost tea, especially in the month leading up to harvest. As heads appear (the bits we want to eat!), a drink of worm wee or liquid fish fertiliser will improve size and shape of the heads. Harvest in 10-16 weeks. Cut flowerhead off with a knife.Compatible with: Dwarf (bush) beans, beets, celery, cucumber, onions, marigold, nasturtium, rhubarb, aromatic herbs (sage, dill, chamomile, oregano)
Avoid growing in same bed: Climbing (pole) beans, tomato, peppers (chilli, capsicum), eggplant (aubergine), strawberry, mustard
Keep well-watered as seedlings. If left without water they will bolt to seed and be inedible. The plants should grow to develop plenty of large healthy leaves, then the green flower heads follow, which are cut for eating. Leave the plant growing after cutting the main flower
head, and get additional crops from the sideshoots which will develop.
Watch for cabbage white butterflies and remove the eggs and caterpillars as soon as possible.
There are two main types of broccoli. The purple sprouting is hardier. The heading varieties cope well with warmer weather.
Once a plant opens its yellow flowers then it is generally past eating. Harvest them sooner rather than later.
a 100 gram serving of raw broccoli provides 34 kcal and is an excellent source (20% or higher of the Daily Value, DV) of vitamin C and vitamin K. Raw broccoli also contains moderate amounts (10–19% DV) of several B vitamins and the dietary mineral manganese, whereas other essential nutrients are in low content.
Broccoli has low content of carbohydrates, protein, fat, and dietary fiber. Boiling broccoli reduces the levels of sulforaphane, with losses of 20–30% after five minutes, 40–50% after ten minutes, and 77% after thirty minutes.
However, other preparation methods such as steaming,microwaving, and stir frying had no significant effect on the compounds. Broccoli also contains the carotenoid compounds lutein and zeaxanthin in amounts about 6 times lower than in kale.