Hop is a group of vines with papery, yellowish-green flowers. Flowers of the common hop are used in brewing beer. The flowers, also called hops, grow in conelike clusters that measure from 1 to 4 inches (2.5 to 10 centimeters) in length. Tiny glands in the flowers and on leaflike structures called bracts contain various oils and resins (sticky substances). These materials prevent the growth of bacteria in beer and give the beverage its bitter taste.
Hopvines may grow as long as 25 feet (8 meters) in a single growing season. The vines die in the fall. But the rhizomes (underground stems) of the plants continue to live, and they produce new vines the next spring.
Hops grow in a wide range of climates and soils. The chief hop-growing countries are Germany and the United States. Washington, Oregon, and Idaho lead the states in the production of hops.
Growers plant hop rhizomes in mounds 6 to 8 feet (1.8 to 2.4 meters) apart. The vines are supported with poles or trellises to keep them from spreading on the ground. Such supports allow the plants to be placed closer together, thus increasing the yield of each unit of land.
Hops are harvested in late summer or early autumn. Usually, workers cut the vines by hand and place them in picking machines that separate the hops from the vines. The hops are then cleaned, dried in ovens, and pressed into bales for shipment or storage.
