I have a customer where I recently did a large install. An 8ft wooden fence was built between this customers lot and the neighbors. The neighbor has perriwinkle that grows through the fence and also it grows under the fence. I have been successful so far with just spraying any shoots that come through but I don't want to deal with it every week or two (yes they are a weekly maintenance customer). My question is what will stop this stuff from coming through the fence and below the fence? Will some type of steel or plastic edging that you drive into the ground work? How hard is it to install? How deep does it need to go down? How long will it take per foot? HELP Please!!!