Prevent fungi from ruining your plants with a fungicide. These products are designed to eradicate fungus on certain types of flowers, shrubs, fruit trees, or vegetable plants. Fungicides can be systemic, meaning the product travels through the plant to control or eradicate the fungus, or contact, meaning the product directly contacts the fungus to kill it. Most fungicides are designed as sprays, to be applied directly to the plant, while many others are in a dust or powder form. Keep fungi off of your plants with a Fungicide.