Purchasing hops for planting
Start with healthy hop plants or rhizomes bought from a reputable source.
October 10, 2012 - Author: Diane Brown, and Rob Sirrine, Michigan State University Extension
Now that harvest season for hops is over, you may be thinking about increasing the size of your hop yard for next year, or maybe you are just starting out and ordering plants for the first time. Hops are a deep-rooted perennial plant difficult to remove once they are established. Growing hops takes a minimum of three years to get a full crop, and a hop yard represents a sizeable investment. There are a number of pests and diseases that you don’t want to get established in your hop yard, including hop stunt viroid and other viruses, downy mildew, Verticillium wilt, crown gall, rootknot nematode and hop cyst nematode.
It pays to start with high quality plants that were propagated from certified stock and to purchase plants from a reputable source. There are many places to purchase hop rhizomes or plants online, and what you get may be of variable quality. You may be interested to know that sales of nursery stock online are regulated just like any other sales. All states have laws that require people selling nursery stock to have a nursery dealer’s license, whether they sell it online or at a physical location or both.
For example, according to Mike Bryan, nursery and export program specialist with the Michigan Department of Agriculture and Rural Development (MDARD), all nursery stock grown in Michigan is inspected at least once a year by highly trained inspectors. MDARD also conducts spot dealer inspections to make sure nursery stock is free of pests and diseases. During these inspections, MDARD staff will also assure that the nursery stock is of the size and grade advertised; that it is the variety described on the label; and that it is being cared for in a manner that will assure the plants will survive.
There are no specific quarantines in Michigan against any pest or disease of hops, but the sale of weakened, dead or dying plants is considered a violation of Michigan’s nursery law. According to state law, the nursery stock being sold must have undergone a visual inspection and be apparently free of pests and diseases. However, bear in mind that not all pests and diseases can be detected from a visual inspection. Your best protection is to purchase plants that have been grown from certified stock and to know your source.
The National Clean Plant Network for Hops (NCPN-Hops), one of five specialty crop groups funded through the Farm Bill, is located at Washington State University’s Agriculture Research and Extension Center in Prosser, Wash. Scientists focus on identifying and eliminating diseases caused by viruses that reduce hop yields and quality. Hops were added to the NCPN in 2010 and since then, many varieties have undergone testing to ensure they are certified disease-free.
The absolute best way to ensure you are starting off on the right foot is to purchase a certified plant from the National Clean Plant Network and have it propagated locally or propagate it yourself. Learn more about which certified varieties are available and how to propagate your own plants.
If you do choose to purchase plants or rhizomes from out-of-state, the Department of Agriculture in the state where the business is located can be contacted if there are questions about whether or not the firm is licensed. For a list of Departments of Agriculture by state, go to the National Plant Board Membership page and click on the name of the state in the list or on the state on the map. Either will bring up the website for that state’s Department of Agriculture and the name of a person to contact to verify whether or not the firm in question is licensed to sell nursery stock.
In summary, bargain rhizomes are no bargain when they come from unlicensed hop nurseries and can be a starting place for introducing diseases and pests into your hop yard.