Garden Update
Week of September 12, 2022
Kathleen Cue, Nebraska Extension Horticulture Educator in Dodge County
Creeping Charlie
Creeping Charlie, also known as ground ivy, (Glechoma hederacea) is a member of the mint family. In lawns this weed readily spreads, weaving between individual turf plants and sending out roots where nodes touch the soil. Creeping Charlie is the most aggressive in shady moist areas but will fill in lawn spaces in full sun areas too. Plants give off a minty odor when mowed or pulled. The leaves of creeping Charlie are round to oval, with scalloped leaf edges. The purplish/lavender flowers appear (usually) in May.
One of the best IPM management strategies for creeping Charlie is to have a dense stand of turf. A thick lawn discourages weed seed germination and naturally muscles out invading weeds. To that end, overseeding the lawn now builds a stronger turf stand. Another helpful practice is to raise the mowing height of the mower to 2.5 to 3 inches to give turf greater resiliency to compete against creeping Charlie.
Fall is an opportune time to use a broadleaf herbicide to manage creeping Charlie and other perennial weeds such as dandelions and bindweed. Fall timing is important because perennial weeds are readying for winter by moving sugars produced in leaves for storage in the root system. We can use the weed’s own physiology against it, making the translocation of herbicides to the roots highly likely and resulting in more effective management of the weed. Plan to get in two applications, spaced per the label directions, before October 31.
Herbicides effective in the management of creeping Charlie include 2,4-D, triclopyr, and quinclorac. Where past applications of 2,4-D alone have done little to manage creeping Charlie, a tank mix that contains 2,4-D and either triclopyr or quinclorac is effective. Stay away from any combination herbicide that contains dicamba, as this can be readily taken in by tree roots and causes long term, sometimes fatal, damage to trees. Read and follow all label directions.
If you miss this window of opportunity to treat creeping Charlie, university research has some good news. This weed is also vulnerable to herbicide applications when plants are in flower.
Photo: Ohio State Weed Lab, The Ohio State University, Bugwood.org
You can find more horticulture information at Trees, Plants and Insects web page.