Broccoli is a bouquet of unopened flowers, and machines still can't pick it
Every broccoli head is a dense cluster of flower buds harvested before they bloom yellow. Its name comes from an Italian word for a cabbage's flowering crest, it was shaped by Roman-era farmers, and despite modern agriculture it is still cut by hand, because no machine can do the job.
Broccoli is a cultivar group of Brassica oleracea, bred from wild cabbage, also called colewort. Farmers around the northern Mediterranean began selecting these crops from about the sixth century BCE, and broccoli itself most likely took shape through selection in southern Italy or Sicily from primitive Roman-era varieties. It reached northern Europe by the 18th century and North America in the 19th, carried by Italian immigrants. The word, first used in English in the 17th century, is the plural of broccolo, a diminutive of brocco, meaning small nail or sprout.
The familiar supermarket type is Calabrese, named after Calabria, with heads 10 to 20 centimetres across on thick stalks. Sprouting broccoli bears many small heads on thin stems, and so-called purple cauliflower is actually a broccoli. Because all these cabbage relatives are one species, they cross easily: Tenderstem, or broccolini, is broccoli crossed with Chinese kai-lan. Rapini, sold as broccoli rabe, is not broccoli at all but a kind of turnip. After the Second World War, American and Japanese hybrid breeding boosted yield and speed.
The plant is a cool-weather annual that grows best at average daily temperatures of about 12 to 20 degrees Celsius. Heat spoils head formation and growth slows below 5 degrees, and how it will cope with long-term heat stress from climate change is still unknown. The season runs 14 to 15 weeks, and after the main head is cut, side shoots produce smaller heads for later picking. California grew 92 percent of US fresh-market broccoli in 2024.
Raw broccoli is 89 percent water and is rich in vitamins C and K. Its bitterness comes from sulfur-containing glucosinolates and their breakdown products; boiling cuts these compounds substantially, while steaming, microwaving and stir-frying leave them largely intact. Preliminary research links how bitter people find it partly to a gene called TAS2R38. A telomere-to-telomere genome, about 633.6 million base pairs across nine chromosomes, was published in 2026.
Source: Broccoli
