Nicotine, a toxic chemical most often associated with cigarettes, has been used as an insecticide since colonial times. One excellent benefit of using nicotine in your garden is that its effectiveness is short lived, but potent. You can kill the critters that damage your plants while saving the ones that protect them. Only a few hours after spraying, you can harvest and eat your vegetables.
Collect cigarette butts. If you smoke, this will be easy, but if you don't you can scrounge them others or from public ashtrays. (Wear rubber gloves when handling them.)
Soak one cup of cigarette butts in one gallon of water for 24 to 48 hours. At 24 hours, check the solution and look at the color. When it looks like iced tea, it's ready. If it's darker, dilute the solution with warm water until it looks like iced tea.
Add soap to your solution. For a long lasting spray, use a two tablespoons per gallon of solution. For spray that quickly dissipates, use half a teaspoon per gallon.
Remove the butts from the solution, then pour the liquid through a strainer or cheese cloth and into another container.
Pour the solution into spray bottles and store it in a cool, dry place out of the sun. It will keep for about a month.