Pocket Botanist
Check these first
- Examine the stems for sunken, discolored cankers.
- Look at the leaves for circular spots with yellow halos.
- Check if the spots are spreading rapidly during wet weather.
Likely causes
Hazelnut Blight
Most likelyHow to tell: This fungal infection creates sunken cankers on the stems and dark, necrotic spots on the leaves. It can eventually kill off entire branches.
What to do: Prune out any infected branches at least 6 inches below the visible canker. Always sterilize your pruning shears with rubbing alcohol between cuts to avoid spreading the fungus.
Leaf Spot Fungi
PossibleHow to tell: These appear as small, circular brown or black spots on the leaves, sometimes with a yellow halo around them.
What to do: Remove and dispose of fallen leaves to prevent spores from overwintering in the soil. Avoid overhead watering to keep the foliage dry.
Find out what's wrong with your common hazel
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 you see cankers on the main trunk or large branches, the tree is in serious trouble. Small leaf spots are usually just a seasonal nuisance.
Stopping it coming back
Ensure your tree has plenty of space for airflow and avoid getting water on the leaves when you irrigate. Clean up all debris under the tree in the fall.
Common Hazel: spots? Check yours with a photo
Every plant is a little different. Take a photo of your common hazel 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 compost the spotted leaves?
- No, do not compost diseased leaves as the spores can survive and re-infect your garden. Bag them up and put them in the trash.
- Is hazelnut blight contagious?
- Yes, it spreads through wind and rain splashes. Pruning infected wood is the best way to stop it from moving to healthy parts of the tree.
Guides to these causes
More problems with Common Hazel
- Why are there bugs on my Common Hazel?
- Why are my Common Hazel leaves turning yellow?
- Why are my common hazel's leaf tips turning brown?
- Why is my common hazel drooping?
- Why is my common hazel dropping its leaves?
- Why is my common hazel not producing catkins?
- How do I fix root rot on my common hazel?
- Why are the leaves on my hazel tree curling?
Back to the Common Hazel 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.