Richgro Black Spot & Fungus Killa protects roses and other ornamental plants from fungal diseases such as black spot, powdery mildew and rust. It is a systemic fungicide that is taken up by the plants roots to control diseases and also contains iron and zeolite which are beneficial to plant health. Because Richgro Black Spot & Fungus Killa is applied dry to the plant there is no mixing or mess or risk of overspray that could potentially harm bees and other beneficial insects.