Pocket Botanist
Check these first
- Inspect the leaves for small brown or black markings.
- Check if the foliage is crowded and preventing airflow.
- Look for signs of moisture lingering on the leaves.
Likely causes
Fungal leaf spot
Most likelyHow to tell: You see small brown or black spots scattered across the leaves, sometimes with a yellow halo.
What to do: Remove and destroy all infected leaves to stop the spread. Apply a copper based fungicide spray every 7 to 14 days during wet weather.
Poor air circulation
PossibleHow to tell: The foliage is very dense and stays wet for long periods after rain.
What to do: Thin out the branches to allow air to move through the center of the vine. Avoid overhead watering to keep the leaves as dry as possible.
Find out what's wrong with your japanese wisteria
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
Small amounts of spotting are common in wet seasons. You should worry if the spots cover more than half of the leaf surface or cause premature leaf drop.
Stopping it coming back
Water at the base of the plant rather than over the leaves and keep the vine pruned to encourage good airflow.
Japanese wisteria: spots? Check yours with a photo
Every plant is a little different. Take a photo of your japanese wisteria 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
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Questions people ask
- Can I leave the spotted leaves on the plant?
- No, it is best to remove them to prevent the fungus from spreading to healthy foliage.
- Is leaf spot fatal to my wisteria?
- It is rarely fatal, but it can weaken the plant over time if left untreated.
Guides to these causes
More problems with Japanese wisteria
- Why is my Japanese wisteria not flowering?
- What are these pests on my Japanese wisteria?
- Why are my Japanese wisteria leaves turning yellow?
- Why are my Japanese wisteria leaf tips turning brown?
- Why is my Japanese wisteria drooping?
- Why is my Japanese wisteria dropping leaves?
- Why is my Japanese wisteria suffering from root rot?
- Why is my Japanese wisteria growing so leggy?
Back to the Japanese wisteria 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.