Ground ivy (Glechoma hederacea), also known as creeping charlie, is a common weed in many lawns. Ground ivy is a low-growing, creeping, invasive perennial. It spreads by seed and the vining stems (stolons) which root at their nodes. The leaves of ground ivy are round or kidney-shaped with scalloped margins. Stems are four-sided. Flowers are small, bluish purple, and funnel-shaped. Ground ivy thrives in damp, shady areas, but also grows well in sunny locations. A member of the mint family, ground ivy produces a minty odor when cut or crushed.
This spring the ground ivy is especially prominent. Some infested areas are a sea of bluish purple flowers.
Non-Chemical Control Options
In small areas, ground ivy can be managed by pulling and digging. This method is best accomplished after a soaking rain or deep watering. Unfortunately, pulling and digging is often ineffective because rarely are all stem and root pieces removed using this method. If the ground ivy is not completely destroyed, surviving portions will continue to grow and spread.
Frequent and persistent removal of ground ivy over the course of several growing seasons as soon as the plant re-emerges may eliminate the weed or keep ground ivy populations low enough to not notice. Persistence is essential to make pulling and diffing successful. Rarely are gardeners consistent and persistent enough to remove this weed by hand.
Herbicides to Use For Control
Control of ground ivy in lawns is difficult. If the ground ivy is not completely destroyed, surviving portions will continue to grow and spread. The most effective broadleaf herbicide products are those that contain one or more of the following compounds; 2,4-D, MCPP, dicamba, and triclopyr. The most effective herbicides to use are triclopyr and 2,4-D.
Triclopyr can be found in Ortho Weed-B-Gon Chickweed, Clover, and Oxalis Killer for Lawns and a few other products. 2,4-D is an active ingredient in many broadleaf herbicide products. As always when using pesticides, carefully read and follow label directions.
Populations of ground ivy vary in their susceptibility to broadleaf herbicides. For example, one population of ground ivy may be highly sensitive to 2,4-D, while another population may be somewhat tolerant to 2,4-D. Since ground ivy populations vary in their susceptibility to broadleaf herbicides, it is important to alternate herbicides or select products with more than one of the effective active ingredients when attempting to control ground ivy.
Apply Herbicides in the Fall
Fall (late September through early November) is the best time to control ground ivy. Spring applications are not as effective. Two broadleaf herbicide applications are necessary to effectively control ground ivy. The first application should be made in late September/early October, the second a month later.
Maintain Healthy Turf to Out-compete Ground Ivy
Once the ground ivy has been effectively controlled, home gardeners should follow sound cultural practices. A good nitrogen fertility program along with the use of herbicides will help effectively control ground ivy. Apply 3 to 4 pounds of nitrogen per 1,000 square feet per year. Nitrogen improves the vigor and competitiveness of Kentucky bluegrass, slowing the spread of ground ivy. An excellent fertilizer program for Kentucky bluegrass lawns consists of applications of 1 pound of nitrogen per 1,000 square feet in late April/May, September, and late October/early November.
Proper mowing, fertilization, and other good management practices should help establish a thick, healthy lawn. A dense stand of grass should help discourage future invasions of this aggressive weed.
Updated from an article that originally appeared in the April 22, 2016 issue of Horticulture and Home Pest News.