Hi there,
I have some otherwise very healthy Resilience lilly pillies that are recently having a problem that started with one plant, but now all 7 seem to have it. The new growth is small and completely curling in on itself. No discolouration anywhere. I can see no mealy bugs, and I can't find a solution anywhere online because every website wants to tell me that the problem is psyllids, which is not what this looks like (it is also a psyllid resistant cultivar).
I really need these trees to keep growing strong as they are a privacy screen, any advice would be very much appreciated!
Leaf curl is caused by insects sucking at the sap on the underside of the leaf (where it is good to hide). I agree that it doesn't look like psyllids in this case as there are no bumps on the leaf where they burrow into it. It could be aphids though or some other sap sucking insect which could be quite small and not easily conspicuous. Try spraying with pyrethrum and ensure it gets on the undersides of the leaves too.
Another solution is to trim off the affected leaves and dispose of in the garbage. This might sound drastic but Syzygium are such fast growers and they are the best at responding to trimming.