SB Plant Invigorator With SB Plant Invigorator, you can treat powdery mildew, use as a pesticide and as a foliar feed. A 3 in 1 easy treatment to use on your roses weekly through the summer during active growth. Safe to be used on all plants including fruit and vegetables as it is a non-chemical/non-biological treatment. SB Plant Invigorator controls mildew in roses and other suffering plants by washing and detatching mildew spores from the surface of the leaf. Use as a foliar feed to encourage shiny and healthy loooking leaves. As a pesticide this controls greenfly, whitefly, blackfly, spider mite, mealy bug and psyllids amongst others. For other natural products that will benefit your roses have a look at Rose Care