Read more: Homemade Weed Killer That Does Not Kill Grass ... neglected spots. The best defense against crabgrass is ...

Crabgrass is best controlled with herbicides commonly referred to as preemergence or preventers. These chemicals kill the weeds as they are germinating before they have a chance to establish.

While Preen is a well-respected brand and has one of the best crabgrass killer products on the market, in any situation where you're uncertain about something you haven't tried before, it makes ...