Humulus

Humulus is a small genus of flowering plants in the family Cannabaceae. It comprises two widely recognized species, Humulus lupulus (common hops) and Humulus japonicus (Japanese hops). Hops are perennial climbers cultivated mainly for the female inflorescences used in brewing and, to a lesser extent, in herbal applications and as ornament.

Description: They are vigorous, twining perennial climbers that may reach several meters in height. Plants have opposite, often lobed leaves and short shoots. The species are dioecious; male and female flowers grow on separate plants. The female inflorescences, called hop cones, are dense clusters of bracts sheltering lupulin glands that produce bitter resins (humulones and cohumulones) and essential oils responsible for aroma.

Distribution and ecology: Native to temperate Europe and western Asia, hops are now cultivated worldwide in temperate regions. They prefer well-drained, moderately rich soils and long daylight hours; crops are typically grown on tall trellises to support climbing bines. Hops can naturalize outside their native range.

Uses and cultivation: Hops are grown primarily for beer production, where alpha acids contribute bitterness and essential oils provide aroma. Varieties differ in alpha-acid content and aroma profile. In addition to brewing, hops have historical use in herbal medicine and as a flavoring and scent plant.

Taxonomy and name: The genus name, Humulus, derives from Latin and is placed in the Cannabaceae with Cannabis. The taxonomy of the group has been refined with molecular data, but Humulus lupulus and Humulus japonicus remain the principal species.