- I'm a stickler for results. That's why I'm glad I found Johnson Yard Master lawn weed killer. No chemicals to mix, no measuring, no bottles. I just attach the disposable can to my hose, turn on the water, and it comes out as a light foam that triggers the weed's own self-destruct mechanism. In no time at all, the weeds begin to die. This lawn had lots of weeds. Then I sprayed it with New Yard Master. Look how beautiful it is now. If you're a stickler for results, get New Johnson Yard Master lawn weed killer. It works hard, you don't.