I tried this yesterday thinking it will never work and blow me I have dead nettles around my hay shed this morning so figured I'd share as its super simple, vinagar, salt and dish soap, thats it! I used perhaps 1l of vinegar with about 1 cup of salt and a good squirt of good ole fairy. The only thing is it apparently stops anything from growing for a while so I wouldn't use where you want grass, great for around buildings though.