Broccoli

Etymology

The word broccoli, first used in the 17th century, 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".

History

Broccoli resulted from the breeding of landrace Brassica crops in the northern Mediterranean starting in about the sixth century BCE. Broccoli has its origins in primitive cultivars grown in the Roman Empire and was most likely improved via artificial selection in the southern Italian Peninsula or in Sicily. Broccoli was spread to northern Europe by the 18th century and brought to North America in the 19th century by Italian immigrants. After the Second World War, the breeding of the United States and Japanese F1 hybrids increased yields, quality, growth speed, and regional adaptation, which produced the cultivars commonly grown since then: 'Premium Crop', 'Packman', and 'Marathon'.

Description

Broccoli is an annual cruciferous plant which can grow up to 60–90 cm (24–35 in) tall.

Broccoli inflorescence grows at the end of a central, edible stem and is dark green. Violet, yellow, or even white heads have been created, but these varieties are rare. The flowers are yellow with four petals.

The growth season for broccoli is 14–15 weeks. Broccoli is collected by hand immediately after the head is fully formed yet the flowers are still in their bud stage. The plant develops numerous small "heads" from the lateral shoots which can be harvested later.

Varieties

There are three commonly grown types of broccoli. The most familiar is Calabrese broccoli, often referred to simply as "broccoli", named after Calabria in Italy. It has large 10-to-20-centimetre (4–8 in) green heads and thick stalks. It is a cool-season annual crop. Sprouting broccoli (white or purple) has a larger number of heads with many thin stalks. Purple cauliflower or violet cauliflower is a type of broccoli grown in Europe and North America. It has a head shaped like cauliflower but consists of many tiny flower buds. Sometimes, but not always, it has a purple cast to the tips of the flower buds. Purple cauliflower may also be white, red, green, or other colors.

Beneforté is a variety of broccoli containing 2–3 times more glucoraphanin and produced by crossing broccoli with a wild Brassica variety, Brassica oleracea var villosa.

Genomics

The first telomere-to-telomere genome assembly of Brassica oleracea var. italica was published in 2026. The genome is approximately 633.6 Mb in size and comprises nine chromosomes. The assembly has a BUSCO completeness of 99.4%, and 58,044 protein-coding genes were predicted.

Other cultivar groups of Brassica oleracea

Other cultivar groups of Brassica oleracea include cabbage (Capitata Group), cauliflower and Romanesco broccoli (Botrytis Group), kale (Acephala Group), collard (Viridis Group), kohlrabi (Gongylodes Group), Brussels sprouts (Gemmifera Group), and kai-lan (Alboglabra Group). As these groups are the same species, they readily hybridize: for example, broccolini or "Tenderstem broccoli" is a cross between broccoli and kai-lan. Broccoli cultivars form the genetic basis of the "tropical cauliflowers" commonly grown in South and Southeastern Asia, although they produce a more cauliflower-like head in warmer conditions.

Cultivation

The majority of broccoli cultivars are cool-weather crops that grow poorly in hot summer weather. Broccoli grows best in an average daily temperature range of 54–68 °F (12–20 °C). When the cluster of flowers (also referred to as a "head") appears in the plant center, the cluster is generally green. Garden pruners or shears are used to cut the head about 25 mm (1 in) from the tip.

The growth of the broccoli head is temperature dependent, with higher temperatures leading to poorer head formation, while growth slows below 41 °F (5 °C). The specific response of broccoli to long-term heat-stress conditions, such as may occur with climate change, remain undetermined.

Broccoli is harvested before the flowers on the head bloom in a yellow color. Broccoli cannot be harvested using machines, but rather is hand-harvested.

Production

In 2024, world production of broccoli (combined with cauliflowers) was 27 million tonnes, with China and India together accounting for 73% of the total (table). Secondary producers, each having about one million tonnes or less annually, were the United States, Mexico, and Spain.

In the United States, broccoli is grown year-round in California, which produced 92% of the crop nationally for sales as fresh produce in 2024.

Nutrition

Raw broccoli is 89% water, 7% carbohydrates, 3% protein, and contains negligible fat (table). A 100-gram (3+1⁄2-ounce) reference amount of raw broccoli provides 141 kilojoules (34 kilocalories) of food energy and is a rich source (20% or higher of the Daily Value, DV) of vitamin C (99% DV) and vitamin K (85% DV) (table). Raw broccoli also contains moderate amounts (10–19% DV) of several B vitamins and the dietary mineral potassium, whereas other micronutrients are low in content (less than 10% DV). Broccoli contains the dietary provitamin A carotenoid, beta-carotene.

Cooking

Boiling substantially reduces the levels of broccoli glucosinolates, while other cooking methods, such as steaming, microwaving, and stir-frying, have no significant effect on glucosinolate levels.

Taste

The perceived bitterness of cruciferous vegetables, such as broccoli, results from glucosinolates and their hydrolysis products, particularly isothiocyanates and other sulfur-containing compounds. Preliminary research indicates that genetic inheritance through the gene TAS2R38 may be responsible in part for bitter taste perception in broccoli.

Pests

The larvae of Pieris rapae, also known as the "small white" butterfly, are a common pest in broccoli and were mostly introduced accidentally to North America, Australia, and New Zealand.

Additional pests common to broccoli production include:

• Aphids
• Cabbage looper
• Cabbage webworm
• Cross-striped cabbageworm
• Diamondback moth
• Cabbage maggot
• Harlequin cabbage bug