Lawns: Winter annual weeds
Do you remember the weeds that were growing in the lawn last spring? Probably not, but henbit, chickweed, and hairy bittercress are just a few of the unwanted, early spring surprises that are waiting for gardeners. These weeds are called winter annuals, which means they germinate in the fall and grow throughout the winter until they flower and disperse seeds in the spring.
Here in western North Carolina, winter annual weeds are already up and growing. They aren’t noticeable yet, but by March they will be large and unsightly weeds in area lawns. After dispersing seeds, these annual weeds die. But their seeds lie on the ground waiting for the fall, when they germinate and start the cycle all over again.
Breaking this cycle is the key to controlling winter annuals. Weeds must be treated before they start to set seeds in the early spring. As soon as you start seeing annual weeds in late fall, spray the lawn with an herbicide that is listed for them. Then spray again in January and February when the temperature is at least 55°F. Look for herbicides containing dicamba, MCPP, and 2,4-D, but check the label for proper application method, timing, and target weed and lawn species.
Timing is critical in lawn weed control. Applying pesticides at the right time can take care of pesky weed problems and leave the lawn weed-free. If you aren’t sure of what kind of weed you have, check the NC Extension Gardener Plant Toolbox, or your local Extension agent can help you with identification if you get samples to an agent while the weeds are still alive. Driving weeds samples around in the car for several days makes identification difficult! For more information on managing weeds in lawns, see the “Lawns” chapter of the NC Extension Gardener Handbook.
— Donna Teasley
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