If your houseplants or outdoor plants have an infestation of destructive insects, ditch the chemical insecticides and reach for red pepper flakes instead. Fill a spray bottle with warm water and add several tablespoons of the spicy flakes. Allow the mixture to sit overnight. Spray the leaves of the plant infected with insects, then wait a few days to see if the infestation cures itself. Insects are not attracted to spicy flavors, so this spray mixture will naturally repel them.