By Gail Oberst
Thinking of growing a few hop plants in your yard, over your trellis or even in a large pot on your front porch? Bravo! There’s nothing more satisfying than pitching your own produce into your boiling brewpot. In Oregon, where hops have grown for centuries, you’ll find fertile growing conditions, especially in the Willamette Valley. But hops grow statewide, including Southern, Central and Eastern Oregon (see cover), although these may need to be watered in the first year.
You can get more information on purchasing rhizomes at http://crosbyhops.com and from other local growers listed at the Oregon Hop Commission’s website. The following guide is condensed from that website, www.oregonhops.org/culture.html. The commission collected the information from Oregon State University and USDA experts, Susan M. Hiller, Gale A. Gingrich and Alfred Haunold.
Of note: Don’t buy hop rhizomes from outside of Oregon, Washington or Idaho if you intend to plant them here. A hop quarantine in the state of Oregon prohibits hop plants and all plant parts from outside those three states. This doesn’t apply to whole kiln- dried cones or pellets that you can buy at your local homebrew shop, or order directly from the grower. This quarantine on rhizomes was established to prevent the introduction of diseases, which could devastate Oregon’s commercial hop production.
About the Plant
The hop plant Humulus lupulus L. is perennial, which means it will produce vines each year, barring disaster. Plant new rhizomes in the spring and vines will grow rapidly, winding around their support in a clockwise direction and clinging with strong, hooked hairs. They reach their ultimate height of 15-25 feet by the end of June when, in response to shortening daylength, vines stop growing vertically and produce sidearms which bear the flowers. Only the female plants produce the cone-shaped “hops” used in brewing. The male plant serves only as a pollenizer, but is not essential for the female plants to produce hop cones. Hops are heterogeneous and new plants coming from seed could be either male or female. For backyard gardeners, it is important to start with rootstock or rhizomes you know to be female. During the first year little growth and few flowers are produced as the plant establishes its root system. A normal crop of hops should be expected the second year.
The hop plant produces best with a minimum of 120 frost-free days. Direct sunlight and long day length (15 hours or more) limits hop production to latitudes between 35 and 55 degrees (that’s generally north to B.C. and south to L.A.). The hop plant requires ample moisture in the spring followed by warm summer weather. In dry climates the hop plant will produce best if supplemental irrigation is provided.
Soil and Plant Nutrition
A deep well-drained, sandy loam soil is best. Fertilizers rich in potassium, phosphate, and nitrogen should be applied each spring. If manure or compost is applied around the hop plant, fertilizer applications may be reduced accordingly.
The soil should be tilled to create a weed-free area. A strong support system is needed for the plant to climb on. Look for space along fences, garage, or property lines. Plant in early spring once the threat of frost is gone but no later than May. The soil should be worked into a fine, mellow condition prior to planting. In cold climates you can plant rhizomes in pots and transplant in June. If planting is delayed, keep rhizomes refrigerated in a plastic bag to prevent them from drying. Plant two rhizomes per hill with the buds pointed up and cover with 1 inch of loose soil. Hills should be spaced at least 3
feet apart if the hills are of the same variety and 5 feet apart if they are different. The first year the hop plant requires frequent light waterings.
When the young vines are about a foot long, select two to six vigorous vines on each hill and remove the rest. Train one to three vines clockwise on a string staked to the hill. Hops mainly grow vertically, but the main concern is to support the vines and prevent the sidearms from tangling. Most cones are produced on the upper part of the plant.
In July, the lowest 4 feet of foliage and lateral branches can be removed to aid in air circulation and reduce disease development. Remove lower leaves carefully to avoid breaking or kinking the main stem. In August allow additional bottom growth to remain to promote hardiness of the crown and plant vigor for next year.
At the end of the season you can bury healthy bottom vines for propagating new plants the next spring. Simply bury the vines in a shallow trench and mark their location. In spring dig them up and cut them into pieces about 4 inches long. Make sure each new cutting has an eye or bud.
For information about treating hop diseases and pests, visit the full version of this document at www.oregonhops.org.
Hop harvest in the Pacific Northwest usually runs from mid-August to mid September, depending upon the variety. If you want to use your hops for ornamental purposes, pick your hops early. Otherwise hand pick hop cones and dry them in a food dehydrator, or use them in fresh hop beers within two or three days of harvest.
To determine ripeness, pick a cone and touch and smell. If the cone is too green it feels slightly damp to the touch and has a softness to its scales. If you squeeze the cone it will stay compressed in your hand. If your hands quickly take up the smell and are slightly sticky due to the yellow powdery lupulin, your hops are ready for harvest.
To harvest, cut the vine at the bottom leaving 3-4 feet of the vine to lay on the ground and cut the string at the top. Lay the vine on the ground and pick off the cones. The harvested vine can be mulched, burned, or woven into a wreath. When handling fresh hop plants, wear long sleeves and gloves because the hooked hairs of the plant may cause a slight rash.
For drying the low-tech way, you can use a window screen. Spread the hops evenly across the clean screen. Place the screen off the ground and in an enclosed area to keep wind and bugs from creating problems. A healthy vine will produce 1-2.5 pounds of dried cones per plant.
The dried hops are ready for storage when springy to the touch and the yellow lupulin powder easily falls out. Another indicator is when the central stem breaks rather than bends. The stem takes much longer to dry than the petals. Cones are best stored in plastic bags that can be sealed. It is important to make sure the cones are sufficiently dry. If cones are not properly dried before storage, they become moldy, wilted, or even rancid and cannot be used for brewing. Fill the bag until the cones are well compressed. Once the bags have been sealed and properly labeled store them in a freezer. Thawing and refreezing stored hops reduces quality and freshness.
Stories from the print edition of the Oregon Beer Growler.