Fuchsia rust, caused by Pucciniastrum epilobii (L) and an example of a leaf spot symptom caused by fuchsia rust (R). | Margery Daughtrey (L), and Ron Jones (R)
In a recent e-Gro Alert, Nora Catlin of Cornell University covers how to spot symptoms and manage the presence of fuchsia rust in your greenhouse. In terms of greenhouse diseases, the proliferation of fuchsia rust is rare, but, especially with dynamic weather changes, it’s not unprecedented, as Catlin notes of cases that have been recorded this very spring.
What Causes Fuchsia Rust?
According to Catlin, “Fuchsia rust is caused by the fungus Pucciniastrum ephilobiim.”
Symptoms of Fuchsia Rust
Initial symptoms of fuchsia rust include pale and discolored leaf spots and patches that can sometimes develop into a tan color with a purple border. This symptom is then followed by “yellow-orange sporulation of the fungus on the under and/or upper leaf surfaces.” Once the disease has progressed to this step, “leaf drop” may occur.
Can Fuchsia Rust Spread to Other Plants?
Thankfully, “rusts are very host specific,” according to Catlin. The only other hosts known to be infected by P. ephilobii are fireweed (Epilobium angustifolium) and true firs (Abies).
Management Practices for Fuchsia Rust
Catlin suggests the following practices to manage the presence of fuchsia rust in your growing operation:
First, infected plants and leaves should be bagged and discarded to prevent/limit spores that can spread the fungus.
Second, fungicides designed and labeled for rust should be applied to the remaining healthy fuchsia plants. Catlin provides several fungicide groups in her report that growers can explore as options for their operations.
Lastly, growers should employ practices to prevent and reduce the spread of new fungal infections, including:
- Keeping humidity and condensation levels low.
- Limiting leaf wetness.
- Maintaining good air circulation throughout the area.
For additional information on managing fuchsia rust in your greenhouse operation, please read the full e-Gro (Electronic Grower Resources Online) alert “Fuchsia Rust.” Additional and current e-Gro alert pieces from Volume 14 (2025) can be found online.