Pocket BotanistCheck these first
- Inspect the undersides of leaves for tiny bugs.
- Look for yellow patches or fuzzy growth.
- Check if the plant was recently moved.
Likely causes
Aphid infestation
PossibleHow to tell: You see clusters of tiny green or black insects on new growth and flower buds. Leaves may yellow or drop as the pests feed.
What to do: Spray the plant with a strong stream of water to knock the aphids off. Use insecticidal soap every 5 to 7 days if the infestation persists.
Downy mildew
PossibleHow to tell: Yellow patches appear on the leaves during periods of high humidity. Eventually, the leaves turn brown and fall off.
What to do: Improve air circulation by spacing plants further apart. Avoid overhead watering to keep the foliage dry.
Find out what's wrong with your western wallflower
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
Worry if the leaf drop is rapid and affects the entire plant. It is normal for a few older leaves at the base to yellow and drop as the plant matures.
Stopping it coming back
Keep the foliage dry and monitor for pests regularly during humid weather.
Western wallflower: leaf drop? Check yours with a photo
Every plant is a little different. Take a photo of your western wallflower 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
- Will my plant grow new leaves?
- Yes, once the underlying cause is addressed, the plant will push out new growth. Be patient as it recovers.
- Is leaf drop a sign of overwatering?
- It can be, as soggy soil prevents roots from breathing. Ensure your soil drains well.
Guides to these causes
More problems with Western wallflower
- Why are my Western wallflower leaves turning yellow?
- Why are there bugs on my Western wallflower?
- Why does my Western wallflower have spots on its leaves?
- Why is my Western wallflower looking leggy?
- Why is my Western wallflower not blooming?
- Why are my Western wallflower's leaf tips turning brown?
- Why is my Western wallflower drooping?
- How to tell if my Western wallflower has root rot?
- Why are my Western wallflower leaves curling?
Back to the Western wallflower 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.