Ag Line: Weed Control in Home Lawns
By Wade Parker County Extension Coordinator

During the winter, we don't usually think about killing weeds in our lawns. However, we do have several weed species that thrive in our lawns this time of year. Unfortunately, winter weeds can often be harder to control. The colder the temperature, the slower the herbicide works when applied.

As homeowners attempt to control winter weeds, the first line of defense is to follow cultural practices that promote vigorous growth and development of your lawn. During the spring and summer is when weed management actually begins. Weeds do not easily invade turf grasses that are properly fertilized, watered, and mowed at the correct height. In other words, if you manage your lawn effectively in the summer, you will have less bare spots for weeds to grow in the winter. Weeds have a hard time competing with healthy Centipede or St. Augustine.

Even though a homeowner does a good job with maintenance, the use of chemical control is still necessary. Many of the weeds that are present now are henbit, chickweed, dandelion, and annual bluegrass. While these weeds are troublesome, they are not hard to control.

Atrazine

Atrazine is one of the most common preemerge herbicides sprayed on lawns to control broadleaf weeds and annual bluegrass. During the winter, atrazine can be applied to Bermuda, Centipede, and St. Augustine. After spring green-up, atrazine can only be applied to Centipdede and St. Augustine. Atrazine does an excellent job controlling lawn burweed, henbit, lespedeza, and many other broadleaf weeds. The addition of Trimac or 2, 4-D can greatly improve weed control. This combination is effective against Florida Betony as well.

Pendimethalin

Pendimethalin is a granular preemerge herbicide that controls most annual grasses and certain broadleaf weeds. It does an excellent job controlling crabgrass, goose grass, and Texas panicum. Pendimethalin can be used on centipede, Bermuda, and St. Augustine as a preemerge herbicide that does best when applied around Feb. 15.

There are many other herbicides that can be applied during the growing season. As a situation arises, please do not hesitate to call the Extension Office.