Pocket BotanistCheck these first
- Inspect the undersides of the leaves for tiny insects.
- Touch the leaves to feel for a sticky residue.
- Look for ants, which often farm aphids.
Likely causes
Aphid infestation
Most likelyHow to tell: You will see tiny green or black insects on the undersides of leaves and a sticky residue on the foliage below.
What to do: Spray the leaves with a strong stream of water from your garden hose to knock them off. If they persist, apply insecticidal soap once a week for 3 weeks.
Sooty mold
PossibleHow to tell: A black, powdery coating appears on the leaves after an aphid infestation.
What to do: Wash the leaves with a gentle soap solution to remove the mold. Focus on controlling the aphids first, as the mold will disappear once the honeydew stops.
When to worry
A few aphids are normal, but if the entire tree is covered in sticky honeydew and black mold, it needs treatment. Healthy trees can usually handle minor infestations without long term damage.
Stopping it coming back
Encourage natural predators like ladybugs in your garden. Avoid heavy nitrogen fertilizers that encourage soft, succulent growth that aphids love.
Not sure which one it is? Photograph your linden tree.
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
- Will aphids kill my Linden tree?
- Usually no. While they are annoying, they rarely kill a mature, healthy tree.
- Is the sticky stuff harmful to my car parked underneath?
- Yes, it can be quite messy. It is best to park elsewhere if your tree is currently hosting a large aphid colony.
More problems with Linden tree
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.