ASK DIARMUID

Q I have had my hibiscus tree for some years but now it seems to be suffering. The few flowers are tiny and there is a growth on the branches.

Should I cut it back now to see if it will recover or should I take it out completely? A I wouldn’t worry about the growth on the branches – that looks like lichen which is a harmless fungus.

To encourage more flowering, I’d prune all branches back by about a third now – this will promote new growth which should flower later in the summer.

I’d also give it a high potash feed which will help flower production as well.