Ground Ivy, or “Creeping Charlie” is probably the most difficult perennial broadleaf weed to control in Iowa. It is an excellent indicator of compacted and poorly drained soils. Ground ivy reproduces by seed and also by rooting on its creeping stems. It was first introduced to the United States as a ground cover alternative in shaded areas. However, its extensive runners (up to 5-10 ft. long) not only began out-competing lawn grasses in the shade, but it quick spread rapidly into full sun.
Ground Ivy is easy to identify with its distinct square and prostrating stems, which readily root at the nodes (as seen to the right from the Scotts grass manual). The leaves are round to kidney-shaped; borne on a short petiole. When crushed or mowed the leaves give off an aromatic minty odor. This aromatic odor often characterizes the Lamiaceae or “mint family” and contains many household cooking spices such as basil, rosemary, and peppermint. Ground Ivy has bright green leaves on an opposite leaf arrangement. The bluish-purple, trumpet-shaped flowers usually appear in May.
The best time to treat ground ivy with postemergence herbicides is when it is translocating carbohydrates deep underground in the late fall and maybe even as late/after the first frost. The late fall application will not yield visible results until the spring. Repeated applications and persistence over multiple seasons may be required for complete control. Even with complete control there is a strong possibility it will move back in rapidly from a surrounding area. A combination of postemergence herbicides containing 2,4-D, dicamba, MCPP and triclopyr provides the best potential control. Below you will find a few additional pictures.