Creeping Charlie (\(Glechoma\) \(hederacea\)) is a persistent, low-growing perennial weed that quickly dominates a lawn, creating a dense mat that chokes out desirable turfgrass. Its aggressive growth and resilience make it challenging to eliminate completely. Successfully removing this weed requires a multi-pronged approach combining physical removal, cultural practices, and targeted chemical treatments. This guide details the necessary steps to identify and effectively manage Creeping Charlie in your lawn.
Identifying Creeping Charlie and Understanding Its Growth
Creeping Charlie, also known as ground ivy, is easily identified by several distinct physical characteristics. The plant features rounded to kidney-shaped leaves with scalloped edges, which grow opposite each other on the stem. A defining trait, shared with its mint family relatives, is the presence of a square-shaped stem that often emits a mint-like aroma when crushed. Small, funnel-shaped flowers, typically blue-violet or purplish, appear in clusters in the leaf axils, usually blooming between spring and early summer.
The difficulty in eradication lies in its highly effective method of spread. This low-growing plant sends out horizontal stems, called stolons or runners, which creep along the soil surface. These stolons root at the nodes as they spread, establishing new, independent plants (ramets) over a wide area. This ability to clone itself means that thorough removal of every piece of the runner system is necessary for successful control.
Non-Chemical and Cultural Control Methods
For small, contained patches, physical removal is an effective non-chemical option. Hand-pulling is the most direct method, but success requires removing every piece of the stolon or runner to prevent re-sprouting. This process is best done after a soaking rain or deep watering, which loosens the soil and makes the entire root and runner system easier to extract.
Altering the lawn environment can weaken the weed’s ability to thrive. Creeping Charlie prefers moist, shady conditions, so improving soil drainage and pruning trees to increase sunlight penetration makes the area less hospitable. Adjusting your mowing height to between 3 and 3.5 inches allows the turfgrass to grow taller, shading the weed and inhibiting its growth.
A specific non-chemical treatment involves applying a solution of borax, which contains boron. Creeping Charlie is highly sensitive to boron, a micronutrient that becomes toxic in slightly elevated amounts. This method is not recommended due to the extremely narrow margin of safety; the difference between the amount that kills the weed and the amount that severely injures the surrounding turfgrass is minimal. Boron is immobile in the soil and does not dissipate, meaning improper application can lead to bare, toxic patches where nothing will grow.
Effective Chemical Treatment Strategies
For widespread or severe infestations, selective chemical control is often the most reliable method for long-term eradication. The most effective broadleaf herbicides contain active ingredients such as triclopyr, or a combination of 2,4-D, MCPP (mecoprop), and dicamba. Triclopyr is highly effective against this weed and is a frequent component in specialized products targeting hard-to-control broadleaf weeds.
The timing of the herbicide application is critical for success, as it must coincide with the weed’s natural nutrient translocation cycles. The single best time to treat Creeping Charlie is in the fall, from mid-September through late October, ideally after the first light frost. During this period, the perennial weed actively moves food reserves down to its root system for winter storage, allowing the systemic herbicide to be drawn deep into the entire plant, including the stolons and roots.
A secondary, effective application window occurs in the spring, typically when the plant is just beginning to flower, around April or May. Multiple applications are usually required for complete control. A common strategy involves applying a triclopyr-based product in the fall and following up with a 2,4-D/MCPP/dicamba combination product the following spring, often with a repeat application a few weeks later. Ensure the product is labeled for use on your turfgrass and follow all safety precautions, avoiding mowing or watering for 24 to 48 hours after application to allow for maximum absorption.
Long-Term Prevention Through Turf Management
Once an active infestation is managed, the focus must shift to maintaining a dense, healthy lawn to prevent recurrence. Creeping Charlie establishes itself easily in thin, weak turf where open patches of soil are available. The most effective long-term defense is a thick lawn that crowds out the weed and denies it the necessary sunlight and space.
Overseeding the lawn with desirable turfgrasses, especially in the fall, is necessary to increase grass density. For shaded areas where Creeping Charlie often thrives, selecting a shade-tolerant turf variety, such as fine fescues, provides superior competition against the weed. A consistent fertilization schedule, particularly one that includes nitrogen applications in the spring and fall, ensures the grass has the vigor to outcompete the weed.
Proper watering techniques also contribute to a strong turf stand. Instead of light, frequent watering, which promotes shallow grass roots and creates the moist surface conditions Creeping Charlie prefers, water deeply and infrequently. This practice encourages the turfgrass to develop deep, robust roots, making it more resilient and less susceptible to weed invasion. Maintaining a higher mowing height, generally between three and four inches, creates a canopy that effectively shades the soil surface, inhibiting the weed’s ability to establish new growth.