Envoke Labeled for Fall New cotton herbicide will be available. Published on: Nov 14, 2006 Tweet Post to Your Wall. Email Story RSS Permalink Print Envoke herbicide recently received a label for fall/early winter application in cotton. "Providing growers with the tools they need to effectively control weeds, including those that are resistant to glyphosate is a primary focus of Syngenta," says Scott Hendrix, Syngenta cotton crop manager. "Fall applications are going to be one of the more consistent ways of controlling horseweed," says University of Tennessee Extension weed specialist. "We've gotten very, very good control of horseweed with low rates of Envoke."