Winter annual weeds, those that show up as young seedlings in the fall and become quite unsightly by mid-winter through spring, will be germinating soon. A pre-emergence herbicide applied prior to their germination is the most effective and efficient way of control.
Pre-emergence herbicides have little to no effect on weeds that have already germinated, so it is important to get the herbicide out soon (Labor Day or soon thereafter is a great target date). A minimum of one-half inch of water either from rain or irrigation should follow shortly after the herbicide application to ensure that the herbicide is activated and moved onto the surface soil to form a uniform weed control barrier.
Pre-emergence herbicides may be purchased formulated as dry granules, wettable powders or water dispersible granules, liquids, and coated on fertilizers. Choose a formulation that is best suited for you and ALWAYS READ THE LABEL for specific application instructions, weeds controlled, and safety precautions.
Extension publications Weed Control Guidelines for Mississippi and Establish and Manage Your Home Lawn provide information to help select the appropriate herbicides for specific weeds and turf species. These publications can be obtained from your local Extension office or downloaded. If your lawn was full of winter annual weeds this past spring, then now is the time to do something about preventing this from happening again this coming spring.
Published September 5, 2011
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. firstname.lastname@example.org