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Check these first
- Inspect the undersides of the leaves for fuzzy gray or white growth.
- Check if the leaves are staying wet for too long after watering.
- Look for yellow patches on the top of the foliage.
Likely causes
Downy mildew
Most likelyHow to tell: You will see yellow patches on the top of the leaves that turn brown or necrotic over time. Look for a grayish fuzzy mold on the underside of the foliage.
What to do: Remove the infected leaves immediately to stop the spread. Improve air circulation around the plant by thinning out dense growth. Avoid overhead watering to keep the foliage dry.
Leaf spot fungi
PossibleHow to tell: These appear as small, circular brown or black spots scattered across the leaves. They often develop during long periods of rain or high humidity.
What to do: Pick off and discard any spotted leaves to prevent spores from spreading. Ensure the plant is in a spot with full sun and good airflow. Keep the soil surface clean of debris.
Find out what's wrong with your lambs quarters
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
Worry if the spots are spreading rapidly to new leaves or if the plant starts losing its vigor. A few spots on older leaves are normal as the plant matures.
Stopping it coming back
Water only at the base of the plant and ensure it has plenty of space for air to move between stems.
Lambs quarters: spots? Check yours with a photo
Every plant is a little different. Take a photo of your lambs quarters 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 still eat the leaves if they have spots?
- It is best to avoid eating leaves with fungal spots or mold. Stick to harvesting the clean, healthy leaves from the top of the plant.
- Will the spots go away on their own?
- No, fungal spots will not disappear. You must remove the affected parts to keep the rest of the plant healthy.
Guides to these causes
More problems with Lambs quarters
Back to the Lambs quarters 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.