rust fungus on Philodendron
Quick answer
If your Philodendron has rust fungus, the most likely cause is: Rust fungus (Puccinia, Uromyces) produces orange-brown pustules on leaf undersides. Spores spread via air currents and water splash in humid conditions with poor airflow.
Start here:
- 1. Isolate plant immediately to prevent spread to collection
- 2. Remove and destroy all infected leaves - do not compost
Why Philodendron gets rust fungus
Philodendron spp.
Rust fungus (Puccinia, Uromyces) produces orange-brown pustules on leaf undersides. Spores spread via air currents and water splash in humid conditions with poor airflow.
How to reverse rust fungus on Philodendron
- 1
Isolate plant immediately to prevent spread to collection
- 2
Remove and destroy all infected leaves - do not compost
- 3
Apply neem oil or fungicide to remaining leaves weekly for 4 weeks
- 4
Increase air circulation with fan near plants
- 5
Reduce humidity temporarily to 40-50% to inhibit fungal growth
Keep rust fungus off this Philodendron
Maintain 40-60% humidity with good airflow. Space plants 12+ inches apart. Inspect new plants before introducing to collection.
Other Philodendron problems
Go Deeper
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