Hops (Humulus lupulus) is a dioecious plant, which means there are separate male and female plants. The female plants produce flowers, called cones, that contain the distinctive aroma and bittering compounds used to brew beer. Plus, this quick-growing plant attract butterflies and can provide shade and privacy as it grows.
There are more than 100 varieties of hops plants, and each variety produces its own flavor and aroma. Hops can grow in most moderate climates, but they do best in USDA zones 5 through 9.
Hops is a vining plant—mature vines can grow as tall as 25 feet—so a trellis system is required for backyard growing. Depending on your space, your trellis system can be as simple as a fence or an arbor, or can be as intricate as a series of tepee-style structures. You can even train the vines to wind around a swing set, if you like.
Here's what you need to know about growing and using your hops plants.
Warning: Hops cones can be toxic to dogs. Do not allow your dog to eat the cones, either fresh or dried.
Planting and Caring for Your Hops
Hops can grow up to a foot per day during the first few months after planting. A single hop plant can produce up to one pound of cones, so several plants are usually sufficient for home brewers.
Hops plants begin as rhizomes (specialized roots) that require well-drained soil with a pH of 6 or 7 and long periods of full sun exposure. In early spring, plant the rhizomes in sets of two per mound with small buds upward about two inches deep.
Frequent shallow watering will help helps establish a healthy root system. After the roots are established, less frequent, deep watering helps increase root growth and drought tolerance. Be sure to water directly at the base of the plants, as wetness on the leaves will encourage disease formation.
Hops vines are heavy feeders and will need a supplemental feeding of compost, manure or commercial fertilizer to remain strong.
Training Your Plants
Once your hops plants have grown to about a foot in height, it is time to begin training them to grow up your trellis system. Hops vines, called bines, grow at a rapid rate. This “training” process helps the bines stay healthy and strong.
Use twine to train the bines to the trellis. Select only vigorous vines to train, and prune away the less vigorous bines. As plants reach the top of the trellis, they will begin to branch put horizontally. It is these horizontal branches that will produce cones.
Harvesting Your Cones
Although you will be able to harvest some cones the first fall after planting, your hops vines will reach their full maturity—with a pound or more of cones per plant—after three years.
How can you tell if the cones are ready for harvest?
Each hops cone grows to a length of one to twoinches with papery green scales. In late summer, pinch a cone. If the texture is papery, the cone is ready to pick. Inside the ripe cone are small, yellow particles, called lupulin, that give beer its flavor and aroma.
Your cones will mature at different times over the next few weeks, so cheek them frequently for ripening. To avoid knocking loose the lupulin, use care when harvesting the cones by using scissors or pruning shears.
Tip: It is a good idea to wear gloves and long sleeves when you harvest because hops plants can cause skin irritation in some people.
Drying Your Cones
After harvesting your cones, it is time to dry them. Simply spread them out in in the sunshine in a single layer on a clean window screen. Make sure you protect the screen from squirrels and other wildlife. Outdoor drying can take anywhere from a few hours to several days, depending on your region's weather.
You also can dry hops in the oven. Set the temperature at 140°F and leave the oven door slightly open to allow moisture to escape. Watch the hops closely to make sure the cones do not become too brittle.
Another option is to use an electric food dehydrator set at its lowest setting (90°F to 100°F).
Your cones are ready for brewing when the central stems are brittle and the lupulin powder falls out easily.
Mature, healthy hops plants can produce about two pounds of dried cones each year. You can use the cones right away for brewing, or you can store them in a sealed container in the freezer for later use.
Continuing After Harvest
As perennials, hops plants die back to their crowns each year, which allows winter sunshine into your backyard. Once you have gathered all the cones, cut back bines to about three feet.
After the first heavy frost, cut the remaining bines at the soil surface and apply several inches of mulch over the crown of each plant.
Because hops plants grow vigorously and can easily take over your garden each spring and summer, you may need to trim their roots back each spring. Sink a spade into the ground in a 12-inch circle around the rhizomes.