Olga from Fort Myers, Fl writes
We in south Florida have approximately 12 plumeria trees some of which reach more than 15 feet tall. In late summer, the leaves start getting rust and soon thereafter the trees look terrible and start defoliating. Will this product help to prevent rust in plumeria leaves? The trees are too tall to spray so we are looking for a product that can be applied to the ground for root absorption by the tree.
While the product label for Bayleton 50 Fungicide WSP does include rust control on certain types of ornamental shrubs and trees, however Plumeria is not included. Additionally, this product has been discontinued by the manufacturer.
Unfortunately, there is not a systemic fungicide listed for preventative control of Plumeria Rust and foliar applications are recommended as this disease typically only targets the leave surfaces and stems. While unappealing, this disease typically does not injure the tree.
General maintenance and care should be be done throughout the year and in late fall/winter to help reduce favorable environments for the disease to develop. Dispose of fallen rust-infected leaves, and spray the ground under the tree in the winter with a copper fungicide, neem oil or horticultural oils during early stages of powdery mildew infection.
Using a fungicide such as Propiconazole or Myclobutanil is recommended in this article on Plumeria Rust by the Manoa Cooperative Extension Hawaii.
For local recommendations on treating Plumeria Rust, we would recommend contacting a local nursery or the Master Gardener at your local county extension office .
Answer last updated on: 12/22/2021
