Pocket Botanist
Check these first
- Inspect the underside of the leaves for fungal growth.
- Check if the soil is staying too wet between waterings.
- Look for signs of poor airflow around the base of the plant.
Likely causes
Leaf Spot Fungus
Most likelyHow to tell: Small dark or tan spots appear on the blades, often with a yellow halo. These spots spread quickly during periods of high humidity or rain.
What to do: Remove the infected leaves immediately to stop the spread. Improve air circulation around the plant and avoid overhead watering to keep the foliage dry.
Rust Fungus
PossibleHow to tell: You will see orange or reddish brown powdery pustules on the leaves. These rub off easily on your fingers.
What to do: Prune away the affected blades and dispose of them in the trash, not your compost. Apply a copper based fungicide if the infection persists.
Find out what's wrong with your timothy grass
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
If the spots cover more than half of the foliage, the plant may struggle to photosynthesize. A few isolated spots are common during wet spring weather.
Stopping it coming back
Water at the base of the plant rather than over the leaves to keep the foliage dry. Ensure your grass has plenty of space for air to move between stems.
Timothy grass: spots? Check yours with a photo
Every plant is a little different. Take a photo of your timothy grass 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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Or go to pocketbotanist.app/get on your phone
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Questions people ask
- Can I save leaves that have spots?
- It is usually better to remove them. Once a leaf is heavily spotted, it cannot recover and may spread the fungus to healthy parts of the plant.
- Will these spots kill my grass?
- Usually no, but it will weaken the plant. If left untreated, the grass will become leggy and lose its vigor.
Guides to these causes
More problems with Timothy grass
Back to the Timothy grass 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.