Hops, the female flowers of the hop vine, a perennial plant native to the Northern Hemisphere. The chief use of hops is in brewing, to add flavor to beer and ale. The hop is a climbing vine that can grow to a height of more than 20 feet (6 m). Its leaves have three or five deep lobes. Male and female flowers grow on separate vines. The male flowers are long, slender clusters; the female flowers are scaly, conelike catkins. These catkins contain various resins and aromatic substances that give flavor to the brew.
Commercial hops are planted in hills about seven feet (2 m) apart. Each hill requires a pole 10 to 20 feet (3 to 6 m) high to support the vines. In some areas, the vines are supported by strings tied to overhead trellises. The hops are picked by hand or machine. They are then dried in kilns (ovens), bleached with sulfur fumes, and pressed into bales.
The hop vine is Humulus lupulus of the hemp family, Cannabaceae.Hops are climbing vines with scaly, cone-like flowers used to flavor beer.