Pocket Botanist
Check these first
- Look for fuzzy or powdery textures on the spots.
- Check if the plant is in a very stagnant, airless corner.
- Inspect the water source you are using.
Likely causes
Fungal Rust
Most likelyHow to tell: Small, rusty or dark spots appearing on the stems in humid conditions.
What to do: Improve air circulation by moving the plant to a breezier spot. Remove the affected stems to prevent the fungus from spreading to healthy parts.
Water Quality
PossibleHow to tell: Small spots appearing after using tap water with high mineral content.
What to do: Try using filtered or rainwater for a few weeks. This prevents mineral buildup that can sometimes cause surface spotting.
Find out what's wrong with your hard rush
The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.
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When to worry
If the spots are spreading rapidly across multiple stems, you must act quickly to prune the infected areas.
Stopping it coming back
Ensure the plant has good airflow and avoid getting water directly on the stems when watering.
Hard rush: spots? Check yours with a photo
Every plant is a little different. Take a photo of your hard rush and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.
Scan with your phone's camera to get the app
Or go to pocketbotanist.app/get on your phone
Get the app · Or check it from a photo now, free
Questions people ask
- Are these spots harmful?
- Yes, fungal spots can weaken the stems over time. It is best to remove them as soon as you notice them.
- Should I use a fungicide?
- Usually, improving airflow and removing infected stems is enough. Only use a fungicide if the issue persists after these changes.
Guides to these causes
More problems with Hard rush
This article was generated with AI on from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.