Pocket BotanistCheck these first
- Inspect the undersides of new leaves.
- Look for sticky residue on the foliage.
- Check for lines of ants traveling up the trunk.
Likely causes
Aphid infestation
Most likelyHow to tell: You will see clusters of tiny green or black insects and sticky honeydew on the leaves.
What to do: Spray the leaves with a strong stream of water to knock them off. If they persist, apply insecticidal soap every 7 days until they are gone.
Ant activity
PossibleHow to tell: Ants often farm aphids for their honeydew, so seeing trails of ants is a major clue.
What to do: Place ant baits around the base of the tree to stop them from protecting the aphids. Once the ants are gone, the aphids are easier to manage.
When to worry
A few aphids are normal, but a heavy infestation that causes leaf curling or soot buildup requires immediate action.
Stopping it coming back
Keep the tree healthy with proper sun and water to help it resist pests naturally.
Not sure which one it is? Photograph your jacaranda.
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 tree?
- Usually no, but they can weaken young trees and cause unsightly leaf damage.
- Can I use neem oil?
- Yes, neem oil is effective, but apply it in the evening to avoid burning the leaves in the hot sun.
More problems with Jacaranda
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.