How to Kill Fungus on Plants

Various types of fungus, the most common being mildew, may appear on houseplants, garden vegetables and other vegetation. Such fungus can retard plant growth or even kill the host plant. Some plant varieties, especially garden vegetables such as lettuce and tomatoes, are especially susceptible. Learn how to kill fungus on plants to restore your plant's health.

Spray bottle

Fungicide

Hydrogen peroxide

Water

Spray the plant with the strongest water pressure possible without damaging the plant. Focus on the leaves and stems that are covered in fungus such as mildew or moss.

Mix one part hydrogen peroxide with nine parts water and pour into a water bottle. Liberally spray all surfaces of the fungi-infected plant with the solution. Repeat daily until all signs of fungi have disappeared. This nontoxic solution is ideal for plants you plan to eat.

Spray a plant fungicide for heavy fungi infestations or as a preventative measure to keep fungi from growing back on your plants. The type of fungicide you use varies depending on your purposes. Spraying neem or jojoba oil is safe for vegetables and fruits and will both kill fungus and keep it from growing back. A sulfur spray (e.g., Safer Garden Fungicide) or biological fungicide (e.g., Serenade Garden) is more toxic than oils. Such chemical fungicides should be used with more caution, and you may want to use them only on plants you do not eat, such as houseplants or ornamental trees and shrubs.

Move infected plants into the sunlight if they are portable. The sun's ultraviolet rays will naturally dry and kill fungus. This can be effective for potted plants and houseplants, but it may not help non-portable plants such as those grown in the ground.

Grow fungus-resistant plant varieties if growing plants such as tomatoes, which are particularly susceptible to fungus.

Biological fungicides may be harmful to your health and the well-being of your pets.