Hell, my calla lily is having a hard time growing and flowering and is losing leaves due to an infestation of small black insects. I have removed them a number of times by shooting them off with a spray bottle or by hand with a wet washcloth, but they always return in great numbers. I'm thinking maybe there is something natural that I can add to my spray bottle that the bugs won't like..? Any suggestions? I need to be gentle as my plant is already in not-so-great condition. Thanks