Creeping Charlie, officially known as Glechoma hederacea, is an aggressive perennial broadleaf weed that can quickly turn a lush lawn into a dense, creeping mat. Because it is a broadleaf weed, it can be selectively targeted with herbicides that do not harm turfgrass. The goal is to employ selective control strategies that kill the weed down to its extensive root system while preserving the health and appearance of the surrounding grass. Understanding the weed’s biology and applying the right chemicals at the optimal time are key to achieving effective and lasting control.
Why Creeping Charlie is Difficult to Eliminate
Creeping Charlie’s structure is specifically adapted to resist common weed control methods, making it a persistent problem. The plant spreads aggressively using above-ground runners called stolons, which root easily at the nodes wherever they touch the soil. This rooting mechanism creates a vast, interconnected network that is nearly impossible to remove entirely by hand.
A significant challenge is the plant’s physical makeup, particularly its leaves. Creeping Charlie leaves possess a waxy cuticle, which acts as a barrier that repels water-based herbicides. This waxy layer prevents many standard products from being absorbed sufficiently to translocate the chemical throughout the entire plant system.
The weed also thrives in environmental conditions that are often stressful for turfgrass, such as dense shade and moist soil. Its preference for these conditions allows it to outcompete and suppress the grass. Because the plant is perennial, it will return year after year unless the entire root system is destroyed.
Targeted Chemical Solutions for Selective Control
Successful chemical control relies on using post-emergent broadleaf herbicides specifically formulated to kill weeds without harming grass. Turfgrasses are monocots, while Creeping Charlie is a dicot (broadleaf), allowing selective herbicides to target only the weed physiology. Single-ingredient herbicides often fail because the weed is tolerant of many common active ingredients like 2,4-D when used alone.
The most effective approach involves using combination products, often referred to as “three-way” herbicides. These mixtures typically contain a blend of active ingredients such as 2,4-D, dicamba, and mecoprop (MCPP), which attack the weed through multiple physiological pathways. Look for products that specifically list Creeping Charlie on the label.
Triclopyr is a primary active ingredient for controlling Creeping Charlie and other waxy-leaved weeds like ground ivy and wild violet. Triclopyr is highly systemic, meaning it is readily absorbed and transported throughout the plant, including down to the roots and stolons. Using a product containing a high concentration of triclopyr, alone or in combination with other broadleaf killers, increases the chance of total eradication.
Optimizing Application Methods and Timing
Proper timing is just as important as chemical selection, as it determines how efficiently the herbicide is absorbed and translocated to the roots. The best time for application is in the fall, specifically between mid-September and early November, ideally after the first light frost. During this period, the plant begins drawing nutrients down to its root system to prepare for winter dormancy.
Applying a systemic herbicide in the fall takes advantage of this natural process, pulling the chemical deep into the stolons and root crowns for maximum effect. A secondary application can be made in the spring when the plant is actively growing, typically from April to June. Two treatments, one in the fall and one in the spring, are often necessary to gain complete control.
To counteract the waxy leaf cuticle, you must add a non-ionic surfactant to the herbicide mixture, unless the product label advises against it. The surfactant acts as a wetting agent, reducing the surface tension of the spray and allowing the herbicide droplets to penetrate the waxy layer. For best results, avoid mowing for a few days before and after treatment to ensure maximum leaf surface area is available for absorption.
Cultural Practices for Long-Term Prevention
Chemical treatments should be complemented by changes in lawn care to create an environment that discourages weed growth. Creeping Charlie thrives in areas with poor air circulation and excessive moisture, so addressing these conditions is important. Improving soil drainage and pruning back low-hanging tree branches will increase sunlight and air movement, making the area less favorable for the weed.
Adjusting your mowing height can also help the grass outcompete the weed. Mowing at the higher end of the recommended range, typically between 3 and 3.5 inches, allows the turfgrass blades to shade the soil surface. This shading reduces the amount of light reaching the low-growing Creeping Charlie, inhibiting its ability to establish new growth.
Maintaining a dense, healthy turf with proper fertilization and watering is the strongest defense against any invading weed. Thick grass naturally leaves less open space for Creeping Charlie seeds or stolons to take root. While manual removal can be done for small, isolated patches, it must be meticulous to ensure all stem and root fragments are pulled out, preventing re-rooting.