i get alot of weeds along edges of my lawns. not all, but quite a few. do think this is due to weed seeds naturally blown on sidewalks, then embedding themselves in the edges, due to wind, etc.. or most likely user error, that i am not over lapping the edges when i apply fertilzers? i'll have nice lawns, with crabgrass/fox tail/ dandelion edging in some areas. opinion?