Q: This year’s rhubarb production is way down with smaller, almost spindly stalks. Others have told us of similar experiences with their rhubarb beds. What is the cause? Is there anything we should be doing this spring or summer or fall to encourage better production next spring?
R. O’C. of Belleville
A: Your rhubarb plants may simply be worn out and need dividing, especially if they have been growing in the same location for five years or more. In the early spring next year, you need to dig the rhubarb plants up and split the crowns into well-rooted pieces with two or more eyes or buds on each division.
Cut out any diseased or dead roots, and replant them in a new location. Choose a well-drained location where tomatoes, peppers, and strawberries have not been grown for several years, as these plants can harbor ‘verticilium wilt,’ which may infect rhubarb plants if they come in contact with this type of soil.
Dig in a few inches of compost, and apply bonemeal if necessary. Plant these crowns two to three inches in depth and at least three feet apart, and keep the bed weeded and watered. You can begin pulling stalks in the first year after transplanting, but don’t go overboard in this harvest.
If you notice small little sting holes on the stalks, they are caused by slow-moving insects — the rhubarb curculio — which are one-half inch to three-quarters of an inch in length and also have a long-snouted beetle. The curculio uses rhubarb only for laying eggs. When the small insects hatch, they will feed on a weed – Curly Dock (Rumex crispus). So learn to identify this weed, and eliminate it as soon as possible to prevent future problems.
Charles Giedeman is a local contributing writer. Send your gardening questions to Lifestyle Department, Belleville News-Democrat, P.O. Box 427, 120 S. Illinois St., Belleville, IL 62222-0427, or email them to email@example.com.
Things to do this week
- This is “Off With Their Heads” week in the case of flowering annuals. By cutting your flowering annuals, the plants will become fuller and produce more flowers in the summer months. Otherwise, your plants will become leggy and not produce as many floral blooms. You can pinch them back about halfway to encourage a more productive flower display.