Pocket Botanist
Check these first
- Check the undersides of leaves for signs of mold.
- Ensure the plant has enough space for air to move around it.
- Remove any fallen leaves from the soil surface.
Likely causes
Leaf Spot Fungi
Most likelyHow to tell: Small brown or black spots appear on the leaves, sometimes with a yellow halo around them. These spots may grow and cause the leaf to drop.
What to do: Remove and discard all affected leaves to stop the spread. Improve air circulation around the plant by spacing it away from others.
Gray Mold
PossibleHow to tell: A fuzzy gray mold develops on leaves or flowers during cool, damp weather. It often starts as water-soaked spots that quickly turn fuzzy.
What to do: Prune away infected parts immediately and dispose of them in the trash, not the compost. Keep the foliage dry by watering only at the base of the plant.
Find out what's wrong with your geranium
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.
Scan with your phone's camera to get the app
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When to worry
If the spots are spreading rapidly to new growth or covering the entire plant, you need to act quickly to prevent total leaf loss.
Stopping it coming back
Water at the base of the plant rather than overhead to keep the leaves dry, and provide plenty of space between plants.
Geranium: spots? Check yours with a photo
Every plant is a little different. Take a photo of your geranium 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
- Is leaf spot contagious to other plants?
- Yes, fungal spores can easily travel to nearby plants through water splashes or air currents. Isolate the affected plant until it recovers.
- Can I use a fungicide?
- You can use a copper-based fungicide if the infection is severe, but cultural changes like better airflow are more effective long-term.
Guides to these causes
More problems with Geranium
- Why are my Cranesbill leaves turning yellow?
- Why does my Cranesbill have bugs on it?
- Why is my geranium not blooming?
- How do I fix root rot in my geranium?
- Why is my geranium growing so tall and thin?
- Why are my geranium's leaf tips turning brown?
- Why is my geranium drooping?
- Why is my geranium losing its leaves?
- Why are my geranium leaves curling?
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.