Ask Mr. Smarty Plants

Calystegia hederacea (Japanese bindweed) is actually native to China. This is another one of those classic stories of an accidentally introduced non-native plant which becomes invasive and difficult to get rid of. It is a member of the Convolvulaceae (morning glory) family. Get some background on this plant from the Ohio State University Extension website Calystegia hederacea. This source states that the primary means of reproduction of this plant seems to be by spreading perennial roots. Apparently this is a big problem in Ohio, because this Columbus Dispatch online article, Tug of War, deals at length with the problems in getting rid of members of the Convolvulus family.

About the only way to deal with it, and there is no easy way, is to starve it to death. It protects itself against destruction by its deep roots, in which food is stored to nourish the plant and keep it spreading. Because of these deep roots, just spraying with a herbicide really isn't effective, the herbicide may damage some leaves but won't get down to the root (sorry!) of the problem. Persistence in just pulling off and pulling up every little beginner plant that comes up will certainly be a step in the right direction, and Spring is the time to do it, because the roots have been supporting the plant all Winter while the leaves were dormant and are low on nutrients. The Lady Bird Johnson Wildflower Center recommends neither for nor against the use of herbicides or pesticides, but this may be a time when you have to resort to tough measures. Do not spray the herbicide, it can easily drift onto more desirable plants and do them more damage that it does the bindweed. It can also contaminate the soil and wash away in rainwater to contaminate nearby water sources. Instead, get a small disposable paintbrush, cut a plant down as close to the root as you can get, and quickly, within 5 minutes, paint the stub with the herbicide.  This permits the herbicide to get into the system of the plant before it heals over, and down to the real problem, the roots. As we said, there is no easy way to eliminate this pest, nor is it a quick process. It no doubt got into your garden from somewhere else in your neighborhood, and it will be back, even if you manage to destroy the roots already there. Keep after it, check the area all the time, and don't let it get ahead of you and shade out valuable, more desirable plants.