I spray the entire plants, you want it good and wet. Place a rag on the top of the soil if you plan to go heavy, which is fine, just don't get too much in the soil. I little overspray on the surface won't hurt anything. You can also cover the plant and spray just a branch or two if you wish.
Thanks for chiming in @pop22 -Is there a preferred technique to spraying them down? Is it ok to spray where the flowers are? Thanks a bunch,I'm a noob and never used it b4