Q: We planted wisteria for its beautiful spring flowers and it grew and grew and took over everything. Now we are trying to get rid of it. New plants are sprouting everywhere — up to 10 feet away from the original plant. Is there a way to rid our landscape of this now wild plant?
A: Chinese wisteria, Wisteria sinensis, can be a big problem to control. I’ve seen entire fields taken over by it. Yet, many people wonder why you would want to kill a beautiful plant like wisteria. It is possible to keep it in bounds for a while (possibly years) in the middle of a lawn with its new shoots arising from roots being routinely mowed. But in many cases, given enough time, shoots coming from roots will escape and then begin to take over — growing on adjacent property, climbing trees, etc.
In order to control an established vine, you must be persistent. Your best bet, outside of moving, is to use a “cut stump” treatment on the main plant and every shoot that sprouts. Use an herbicide that contains triclopyr. Some brand names include: Enforcer Brush Killer, Ortho Brush-B-Gon, Ferti-lome Brush Killer-Stump Killer, Garlon (forestry use) and Remedy (farm use). Cut the main stem (trunk) as close to the ground as possible and as level as possible to facilitate application of the herbicide to prevent sprouting. It is critical to immediately apply the product to the freshly cut “stump.” Stumps that are not treated with the herbicide will sprout.
When using any pesticide, including herbicides, always read and follow the label directions and precautions. When using any triclopyr product, be very careful to not get the product on adjacent desirable plants, including their roots Never leave the open container setting on the ground. A better option is to place the open container in a waterproof plastic pan so that any spill will be contained within the pan. Misuse of this herbicide can result in the death of nearby trees and shrubs.
Other invasive, undesirable woody plants can be controlled using this method such as Chinese Tallow (popcorn tree), Chinese Privet (Ligustrum sinensis) and Japanese Honeysuckle (Lonicera japonica).
You will find additional information on controlling non-native exotic plants that are invasive at http://edis.ifas.ufl.edu/wg209 or by contacting the University of Florida’s Institute of Food and Agricultural Sciences Extension Office in your county.