Pocket Botanist
Check these first
- Look closely at the leaves for white dust or fuzzy growth.
- Inspect the undersides of leaves for slugs or snails.
- Check if the plant is crowded by other foliage.
Likely causes
Powdery Mildew
Most likelyHow to tell: You see a white, powdery substance on the surface of the leaves.
What to do: Improve air circulation by spacing plants further apart. Apply a neem oil spray or a fungicide specifically labeled for powdery mildew.
Slug Damage
PossibleHow to tell: Irregular holes or chewed edges appear on the foliage, often accompanied by slime trails.
What to do: Handpick slugs in the early morning or evening. Use copper tape around the base of the pot or apply iron phosphate slug bait.
When to worry
If the spots cover most of the leaves, the plant will struggle to photosynthesize. Small, isolated spots are usually manageable with quick treatment.
Stopping it coming back
Water at the base of the plant to keep leaves dry and ensure the plant has plenty of space for airflow.
Not sure which one it is? Photograph your harebell.
This page lists the usual causes. Pocket Botanist looks at your actual leaf and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.
Questions people ask
- Can I wash off the white spots?
- You can wipe them off, but the fungus is likely still present. Use a fungicide to treat the underlying infection.
- Are slugs common on harebells?
- Yes, especially during wet weather. They love the tender foliage of the harebell.
More problems with harebell
This article was generated with AI from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.