Daylily Rust—Puccinia hemerocallidis
Daylily rust is a fungal disease that causes leaf damage in many varieties of daylilies. It is mainly a matter of aesthetics because it doesn't kill most varieties. Some varieties are less susceptible to damage than others.
Yellowing of the leaves is a symptom of rust. Daylily rust contributes to the poor health of plants by allowing less photosynthetis and increased water loss.
Raised yellow-orange to rust-brown pustules on leaves, most prominent on the undersides.
Daylily rust is a fungus with a complex life cycle, but it can re-infect daylilies without its alternate host.
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Identification and Control Information
- Pest Alert: Daylily Rust (PDF)—University of Wisconsin–Madison
- Fact Sheet with Symptoms and Management Strategies—Cornell University Plant Disease Diagnostic Clinic
- Daylily Rust Information Page
[Photos: Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services, Bugwood.org]