Essential oils contain powerful properties that can help keep your garden bug-free, the natural way. This simple recipe uses the power of peppermint oil to ward off unwanted visitors, keeping your home and garden happy. Simply fill a 16-ounce glass spray bottle with water, leaving an inch or so of room at the top. Add 15 drops of peppermint oil and shake well before each use. Apply spray to every plant in your garden, making sure to cover the stems and undersides of leaves as well. Spray again after each rainfall.