Hops

Sowing: Hops is most often started from dormant rhizomes planted about 2 to 4 inches deep and spaced roughly 3 to 5 feet apart, though hardened-off potted plants can instead be set 2 to 3 feet apart once the danger of frost has passed. Choose a full-sun site with good air circulation and well-drained sandy or silt loam soil.

Support: Because hops climbs by twining bines that wrap clockwise around whatever they touch, a tall support is essential; commercial growers string twine from cables between 18-foot poles, while home gardeners can use fences, arbors, or strings run from a rooftop, allowing 15 to 25 feet of vertical room.

Watering and feeding: Consistent moisture matters most while plants are becoming established, though soil can be allowed to dry slightly between waterings once mature, since hops tolerates drought once rooted in but grows best with supplemental irrigation, needing several gallons a day for an actively growing plant in hot weather. A balanced or high-nitrogen fertilizer is typically applied at the start of growth and again through the season.

Maintenance: In the first year growth goes into roots and rhizomes rather than cones, so plants are left unpruned; from the second year on, the earliest spring shoots are cut back to the ground to spur stronger regrowth, and only two to four bines per plant are kept while other suckers are removed. Hops needs about three years to reach full production, and the top growth dies back to the roots each winter, after which the old stems are cut away.

Pests: Aphids can crinkle leaves and coat them with sticky honeydew that fosters sooty mold, and are controlled with a strong water spray or insecticidal soap; Japanese beetles, potato leafhoppers, and spider mites are also reported on the crop. Root-knot nematodes can damage plantings and cut yields, which sometimes leads growers to use containers or raised beds instead of open ground.

Diseases: Powdery mildew and downy mildew are the most common pathogens, and are discouraged by good air circulation, avoiding overhead watering, and stripping the lower leaves from bines once they are trained onto their support; leaving bines overcrowded and unpruned increases disease pressure.

Handling: Contact with the plant's bristly stems and foliage can irritate skin, so gloves and long sleeves are recommended when training or picking it.

Picking: Cones are harvested from mid-August into September, with a prime window of only seven to ten days, and it is better to pick a little over-ripe than under-ripe. Ripe cones feel dry, papery, and springy, smell of cut grass or onions when rolled between the hands, and show golden-yellow lupulin, while immature cones stay compressed with a vegetative smell and over-ripe cones turn orange and rancid; in a plant's first year cones should be handpicked to avoid disturbing the roots, and the bines are left standing until they die back in winter, whereas on mature plants cones are picked by hand or the whole bine is cut two to three feet above the ground first, with a mature plant typically yielding one to two pounds of cones.

Storage: Fresh cones can be used directly for a wet-hopped beer, but are more commonly dried for later use, and on a larger scale are kiln-dried, baled, pelletized, then vacuum-sealed and frozen until sold.

Culinary: Hops' dried cones are the primary flavoring and bittering agent in beer, their lupulin glands supplying the acids and oils that give brews a pine- or citrus-like aroma, and the same cones have also been used to flavor herbal teas and soft drinks.

Ornamental: Beyond brewing, hops is grown as a fast-covering ornamental vine for arbors, fences, and archways, valued for its fragrant flowers and, in some plants, colorful foliage.

Other: The plant has also been used historically as a livestock feed supplement, a preservative, and for medicinal purposes, and has been noted as a source of dye and fiber.

Hops occurs natively across much of the Northern Hemisphere, with wild populations ranging from Europe through Siberia and northern Iran to North Africa, and native stands also found in North America. Its cultivation is documented as early as 736 AD in Bavaria, and hop-growing reached the American colonies by 1648, when plants grown in Massachusetts supplied the first commercial brewery there.