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Check these first
- Inspect the undersides of the leaves for raised bumps.
- Check if the spots rub off as a fine powder.
- Look for signs of overcrowding in the plant clump.
Likely causes
Rust Fungus
Most likelyHow to tell: You will see small, raised orange or brown bumps on the undersides of the leaves. These bumps eventually release a fine, rusty powder.
What to do: Remove and destroy all infected leaves immediately to stop the spread. Improve air circulation around the plant by thinning out dense foliage. Avoid overhead watering to keep the leaf surfaces dry.
Leaf Spot Disease
PossibleHow to tell: These spots are usually darker, often brown or black, and may have a yellow halo around them. They appear as flat lesions rather than raised pustules.
What to do: Prune away the affected leaves to prevent further infection. Ensure the plant is not overcrowded and has plenty of space for airflow. Keep the foliage dry when watering.
Find out what's wrong with your clustered dock
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 cover more than half of the foliage, the plant will struggle to photosynthesize and may decline. A few small spots are manageable with quick pruning.
Stopping it coming back
Keep the leaves dry by watering at the base of the plant instead of over the top. Provide plenty of space between plants to ensure good airflow.
Clustered dock: spots? Check yours with a photo
Every plant is a little different. Take a photo of your clustered dock 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.
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Questions people ask
- Can I save a leaf with rust spots?
- It is best to remove it entirely. Once the fungus starts producing spores, it spreads very quickly to healthy parts of the plant.
- Will these spots kill my plant?
- Usually not, but it will weaken the plant significantly. If left untreated, the plant may lose its vigor and stop growing well.
Guides to these causes
More problems with clustered dock
Back to the clustered dock guide
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.