We all know a weed when we see one, popping up in our lawns, spoiling our landscape’s beauty. Some weeds require certain methods to eliminate them, so it is helpful to know what weeds you are encountering. Weeds are classified as either annual, where the growth cycle is only one season, or perennial, where the growth cycle is two years. Annual weeds are further classified as summer or winter. Winter annual weeds die when the weather turns warm, and the summer annual weeds die in the fall. Houston weeds are often winter annuals, as the heat here will kill off almost any plant!
Some grassy weeds include bluegrass and crabgrass. Bluegrass, a light green, bunchy looking weed that spreads, is one of the most common weeds in Houston. It is a “winter weed” and will disappear as the weather gets warmer, but can be eliminated with a pre-emergent herbicide in the late fall. Crabgrass is the bane of most residential homeowners and is a tough weed that can proliferate and choke out your Houston lawn if not eliminated. A pre-emergent herbicide can be used in the early spring.
Broadleaf weeds include spurweed and buttercups. Spurweed is a waxy weed with spiny parts that can hurt your feet if stepped on. It is another winter weed and will vanish once the weather gets warmed, but can be treated with a pre-emergent in the early fall. Buttercups thrive and spread in the early spring and will continue to pop up, as they are perennial weeds, if you don’t treat them. You can treat this weed with the same pre-emergent herbicide you used for spurweed.
Nutgrass is one of the most invasive weeds known, having spread out to a worldwide distribution in tropical and temperate regions. Ranking right up there with poison ivy, it has been called “the world’s worst weed” as it can be found in over 90 countries and infests over 50 crops worldwide. Herbicides are not effective, as they will only kill the leaves, and pulling only breaks the roots at soil level, and it will grow back by the next day. Weed killers like Roundup, containing glyphosate will kill some of the tubers and repeated application can be successful. Halosulfuron, brand name “SedgeHammer”, will control nut grass after repeated applications without damaging your lawn.
Once you have identified your weeds, you can use these steps to control them. You can dig them up, eliminate them with sprays, even mix your own sprays with either bleach and water or lemon juice and vinegar. Just make sure to avoid spraying your healthy plants while treating your weeds. Your best defense against weeds is keeping a healthy lawn by keeping it watered, cut weekly, and fertilized a couple of times a year.
Ashleigh Argo, Office Assistant of Arning Lawns