So some of my clients power edge and some have contractors do it. This destroys the crabgrass control along the edge. Usually. I think I have seen some serious cases of this problem. I apply crabgrass control to my various clinets properties from about March 15 to April 30. But...what to do. Should I ask them to skip power-edging entirely? Skip till August? Skip till July? Is it OK in cool months like May?