Organocide Plant Doctor is a Systemic Fungicide used to control and prevent a wide variety of diseases that affect vegetable gardens, bedding plants, ornamentals, roses, fruit trees, shrubs and lawns. Plant Doctor's systemic action means once the product is applied it travels to all parts of the plant roots, stems and leafs to protect and treat disease such as black spot, powdery mildew, blights, root rot, and much more.