My Noni plant has sooty mold
My Hawaiian Noni plan started to develop on the leaves, and on the stem. When I asked the plant expert at chalet Garden shop in Wilmette, she said that it was sooty black mold. It is a type of mold that grows in the secretions of honeydew that is produced by many different types of common houseplant pests. In my case, I have a problem with spider mites. She could tell that it was spider mites because there were also holes in the leaves of the plant.
The best way to get rid of the sooty black mold is to get rid of the spider mites, or whatever past is producing the honeydew secretion. Although the mold is not harmful to the plant, the insect that it needs in order to grow, can kill the plant. At the first sign of sooty mold, the pest that is producing it should be located, and eliminated.
Neem oil is a good treatment for both the pests, and the sooty mold. Spider mites have been a big problem for me this year. I keep on treating my plans for them, and they keep on coming back all the time.