My husband planted ground ivy on our boulevard. If you are not familiar with ground ivy it is also known by other names; gill on the ground, Creeping Jenny and most notoriously, Creeping Charlie. Lawn purists may be horrified, but I quite like it. It has a bad reputation, mostly because it is very invasive and can choke out the lawn if left unchecked.
Creeping Charlie is a perennial, low growing ground cover that thrives in moist, shady spots such as under trees and shrubs. It thrives in nutrient poor soil. The vine has round or oval scalloped leaves and produces tiny, blue/lavender tubular flowers in the spring and early summer. It has other benefits, including forage food for bees in April and May. It is edible and medicinal. On the east coast it is often included in no-mow seed mixes.
It is easy to grow, but if you are person who favors a uniformly green lawn, then Creeping Charlie is your nemesis. It’s a member of the mint family (and we know how mint spreads). It seldom stays put and can also do quite well in sunny spots if your lawn is thin. Planting it on the boulevard will keep it contained from spreading to any neighbors’ yards.
Creeping Charlie is not native to Minnesota. It is native to Europe and was introduced in America, emerging in New England as early as 1672. It was also known as alehoof and was used in producing ale before the wide use of hops. The stems are square and the flowering stems grow vertically. The stems that grow horizontally above ground are called stolons. At nodes on the stolons, roots are sent down and grown horizontally underground. This is how Creeping Charlie spreads.
The best way to control Creeping Charlie is to maintain a healthy lawn by mowing regularly and properly fertilizing, watering and reducing the amount of shade in your yard. Grass needs plenty of sun, which is why it is difficult to grow under trees, shrubs or shady spots. (If you want to grow grass in less than full sun be sure you are seeding shade tolerant varieties.) Proper lawn maintenance results in a thicker more vigorous lawn, where it is more difficult for Creeping Charlie to invade. If it does creep into your yard, and you catch it early you can pull it out by hand. However, if there is more than you can pull out by hand, try a dethatching tool, also called a power rake or vertical mower. This tool combs the grass making small cuts into the soil and roots that allows you to rake out the Creeping Charlie. You will also lose some of the grass as well, so the best time to do this is mid-August to mid-September, which is also the best time to reseed your lawn.
A chemical herbicide can also be used on Creeping Charlie. One that has the active ingredients of two, 4-D and MCPP, will kill all woody or broad leaf vegetation it comes in contact with. If you use one of these be careful of the vegetation surrounding the “weed” you want to eradicate. Apply the herbicide on a day when the temperatures are in the 60s and 70s, there is no rain predicted for 48 hours, and there is little or no wind to avoid drifting the chemical to desirable plants. An herbicide that also contains dicamba may be more effective against Creeping Charlie because it is absorbed through the plant’s roots, but because of this it should not be used where there is a possibility that the roots of trees, shrubs or other plants could also absorb the herbicide. A more recent herbicide product available to homeowners contains the active ingredient trichlopyr. It is usually more effective on some difficult to control weeds. Be sure to select the product for use on lawns and not the formulation for general broadleaf vegetation control in non-lawn areas. If Creeping Charlie is pervasive you may wish to start over removing all vegetation and reseeding the whole lawn.
When using herbicides for Creeping Charlie control, you will usually get better results applied in the fall (mid-September to early October) rather than spring or early summer. However, if you need to achieve some control during spring and summer, consider doing two or three repeat applications about two to three weeks apart. Long term control with spring and summer applications is rarely achieved with only one application. Remember to always follow product label directions for proper use.