White mold is a common disease in plants that affects over 400 species. If untreated, it can cause the stem to rot, resulting in death. The good news is not all mold is lethal, but knowing the type infecting your plants makes it easy to remedy mold problems helping your greens thrive and stay healthy. Future infestations are also prevented by following good plant maintenance and pest management practices.
Molds Appear in Different Forms
One of the most common mold that appears on a wide species of plants is gray mold. It thrives during damp to mild or cool weather. Spores germinate in temperatures between 45-60°F and 93% and above humidity levels. Healthy plants do not easily get contaminated, but can enter through wounds on establishing plants.
Black mold or sooty mold is a fungus that covers twigs, branches, or leaves in black soot. It is the honeydew or secretion of pests such as aphids or scale dump on your plants. Sooty mold is not lethal to plants unlike black mold found in the environment that can cause respiratory problems, chronic fatigue, and persistent headaches in humans. As such, mold removal in homes and buildings is critical in avoiding exposure to spores and toxins that can cause rare complications, such as convulsions.
Another common mold found in plants is white mold or powdery mildew. Caused by airborne fungus or spores, it attaches itself to a young leaf and quickly spreads to other parts of the plants. Nearby plants are also infected. White mold thrives in warm, humid areas. Although it will not cause an established plant to die, it can weaken it and reduce growth.
Treating Plant Mold
Gray mold in plants thrive in damp conditions so it is recommended to prune or stake plants to improve air circulation. Ensure that pruning tools are disinfected after each cut to avoid spreading the mold to other plants. If you have indoor plants that are infected with gray mold, improve air flow by investing in a small clip-on fan. An organic fungicide can also eliminate the disease.
Horticultural or insecticidal soap can control the spread of powdery mildew. You can also try a home remedy by mixing 1 teaspoon of baking soda with a quart of warm water. In addition, plants should be well-spaced to improve air circulation and reduce humidity levels around them.
Meanwhile, black mold is treatable using neem or horticultural oil. Avoid spraying the solution to the plant in direct sunlight as you risk sunburning the leaves during treatment. Remove the soot by spraying with a solution of dishwashing liquid that will clean up the mold and kill pests that cause it.
Preventing Future Infestation
Since mold thrives best in damp and humid conditions, improving air flow is highly desirable. It also makes it easier to manage diseases. Before planting new ones, ensure that you they have adequate spaces in between for good air circulation. Avoiding overwatering to reduce humidity at the canopy level can also help, as watering in the early morning hours to give plants time to dry out. Regularly inspecting leaves, stems, and branches to detect the presence of mold also gives you the chance to remedy the problem quickly and prevent further infestation.
The presence of mold in plants is often unsightly and can affect the growth and health of your greens. By removing and controlling mold infestation, you can have beautiful and healthy plants again.

Photo by Benjamin Combs on Unsplash
Author: Jenny Holt
Jennifer Holt is a freelance writer and mother of two, who loves nothing more than to play, “where has the cat hidden itself now.”