Purdue Extension Service

Vanderburgh County, Indiana

Dandelions and Other Lawn Weeds

By Larry Caplan, Extension Horticulture Educator, Vanderburgh County, IN

For the Evansville Courier and Press, April 19, 2009

When I was a kid, I learned the following riddle: "If April showers bring May flowers, what do May flowers bring? Pilgrims!"

Yes, even as a youth, I had a very "unique" sense of humor....

Indeed, there are many flowers springing up as a result of April showers. Alas, not all of them are equally welcome. Dandelions, for example, create a love/hate relationship with many gardeners. Many people enjoy the yellow blooms, considering them further proof that spring has, indeed arrived. Some folks know how delicious and nutritious dandelion greens are, if they are harvested before the blooms are produced. And a select few enjoy making (and drinking) dandelion wine.

Here's a bit of trivia: the name "dandelion" is a corruption of the French "dent-de-lion," which translates to "lion's tooth," in reference to the jagged edges of the leaves.

But for most gardeners, dandelions are not wanted, and are relegated to the "weedy" side of the plant kingdom. Their appearance in the lawn is considered an insult to person's gardening abilities. Dandelions can serve as an alternate host for several virus diseases, including aster yellows, which has become fairly common on black-eyed Susan and related plants.

One of the best ways to control this weed is to promote good turf growth. Proper watering, fertilizing and mowing will help the turfgrass squeeze out weeds, including dandelions.

Chemical control is often used...incorrectly... to control dandelions. Most folks start spraying herbicides as soon as the yellow flowers make their appearance, which is the wrong time of year. The best time to control dandelions and other broadleaf weeds is in the fall; the second most effective time is in late spring, at or shortly after the flush of flowers. According to research at Purdue, herbicide applications before mid-April will only "burn" the leaves back; the weeds will grow back by summer.

Herbicides containing 2,4-D, MCPP and dicamba are most effective for control of dandelions and other broadleaf weeds. If you only have a few dandelions in your lawn, consider spot-applying an herbicide with a spray bottle rather than treating the whole lawn. We do not need to use any more herbicides than what is absolutely necessary on our lawns. Be extremely careful when applying any herbicides near ornamentals! Spray drift, or even uptake of herbicide runoff by the plant's roots, can easily cause damage to nearby shrubs and flowers.

If you wish to avoid using herbicides, hand pulling can control these weeds. You must be sure to remove all of the tap root, or the plant will simply grow back. Various tools exist to make this job easier, but the best idea is to try pulling the weeds when the soil is moist. This way, the tap root is more likely to slide out of the soil, rather than snap.

For more information on lawn weeds, contact the Purdue Extension Service at (812) 435-5287.