I dont know about citric acids but the cigarette trick is better with chewing tabacco. Either way just fill a mason jar 1/4-1/2 full with tabacco and then fill with water close and leave outside to bake in the sun for a few days. Its even better if you go out and shake it up every now and then. Then just pour it on and around. Be really generous if you want to make sure there gone but remember your getting niccotine to the girls roots so theres loss too.