I was surprised to learn that the International Herb Association had named hops (Humulus lupulus) Herb of the Year™ for 2018, largely because I’d never thought of hops as a herb. But then, if it’s not a herb, what else would you call it? So I suppose they’re right!
Hops is most famously grown as a flavoring and stabilizer for beer, but also as a medicinal plant, notably as a treatment for anxiety, restlessness, and insomnia. Hop pillows, for example, are said to have a sedative effect. Considering that the hop plant is in the marijuana family (Cannabaceae), one might suppose users can expect relaxing dreams!
Curiously, hops is poisonous to dogs and, to a lesser degree, cats. Leaves and stems are not a problem, but do keep hop cones out of their reach.
Big and Vigorous
Gardeners should be aware that hops can be a thug of a plant. It’s a herbaceous perennial, dying back to the ground each winter, but growing right back up in spring. It’s a twining vine that can reach 25 feet (7.5 m) if given a tall enough support. It also produces numerous offsets, often several feet (a meter or so) from the mother plant. Ideally, you’d keep them under control before they take over your yard!
Hops is very hardy, growing from zones 3 to 8. It’s an adaptable plant, thriving in most well-drained soils, although does best in temperate conditions, in rich soil of moderate pH that remains somewhat moist at all times. Full sun is best in most areas, but it does better in partial shade in hot summer climates. Mulching is wise, especially in drier climates.
Hop plants are dioecious, producing male and female flowers on separate plants. It’s the glands rich in essential oils from unpollinated female flowers that are used both as flavoring and medicinally. Not only do male plants not produce cones—the bract-covered flower clusters that are harvested—but they decrease the quality of female cones by pollinating their flowers, so male plants are culled out to prevent unwanted pollinisation.
Most home gardeners really only need one hop plant, although if you’re seriously into beer-making, two or three might be necessary. You can grow hops as an ornamental vine, allowing it to clamber up a robust trellis or any other support it can wrap its twining stems around: it will not cling to walls on its own.
The lobed maple-shaped leaves are not unattractive and the pale green drooping cones, held out like so many earings, add further charm at the end of the season. Golden hops (the female cultivar H. lupulus ‘Aurea’ and others), with yellow-green leaves turning greener as the summer advances, is a popular ornamental variety, but doesn’t produce quality cones.
You’ll find potted potted hop plants in local nurseries that you can plant from spring to fall. Mail-order sources usually offer a much wider range of clones (there are literally dozens of cultivars, each with its own unique properties) and usually offer rhizomes for planting in early spring. Look for plants certified virus-free. Plant rhizomes about 6 inches (15 cm) deep.
Hops can also be grown from seed, but that’s not recommended, as not only will you have to cull out the male plants, but even the female ones will probably produce cones of inferior quality. Serious hops growers will only grow cultivars recognized for their exceptional productivity of quality cones.
If home gardeners typically grow hops up trellises, pergolas and other ornamental structures, hops farmers grow them up wire or string supports in long rows using solid posts to hold the wires up. Typically, they plant them 7 to 8 feet (2 to 2.5 m) apart at first, as offsets quickly fill in any bare patches.
Apply compost early each spring or fertilize with a slow-release organic fertilizer: hops are voracious feeders.
Later in the spring, when the bines (as hops stems are called) are about 1 foot (30 cm) tall, cull out the weakest ones and direct the others to the nearest support (if they haven’t already found it). Then just let the plant grow, with summer care usually being limited to watering during periods of drought. Most plants will produce lightly the first year, more in the second and heavily starting in the third year.
Harvest the cones in late summer or early fall when they become papery to the touch and the bracts start to turn yellow on the edges. By then, the lupuline glands that contain the essential oils, readily visible it you lift up the bracts, will be yellow and fragrant. Dry the cones on a screen in a shady spot indoors or in a garage for a few days. They can then be stored frozen in a sealed bag until needed.
As winter approaches, frost will kill the vines back. Some gardeners then cut them to the ground immediately; others leave them up for the winter and cut them back in spring.
Pests and Diseases
Homegrown hops are rarely affected by diseases, although there are several that can attack commercial plantings. To avoid problems, always buy plants certified free of disease.
Slugs or snails may cause minor damage in the spring, but generally the fast-growing plants quickly outpace them.
Japanese beetles, hops loopers and other leaf-eating pests are not uncommon, but the plants will still produce well as long as damage is minor. Spraying with neem or insecticidal soap can help keep damage low. For more on controlling Japanese beetles, read Controlling Those #$@&%*Japanese Beetles.
So there you go! Hops are easy to grow: in fact, almost too easy! Keep a machete on hand at all times!