Matchweed is a mat-forming perennial with opposing leaves on hairy branching stems. Leaves have small teeth at the outer tip. The purple to white flowers emerge around the tip of the seed stalk forming a “match head” appearance. Matchweed spreads by both seeds and stolons along prostrate stems. Matchweed occurs from the transition zone to the southern coastal areas and beyond, including Hawaii, Mexico, and Central and South America.
Since matchweed prefers low moist areas and is found near limestone outcroppings, improving aeration and lowering soil pH may assist in preventing infestations of this prostrate perennial.
Use a selective post-emergence herbicide suitable for the turf species infested. For optimum control, make your herbicide application when matchweed is actively growing and in the four leaf to flower stage of growth.