Three of our six dwarf date palms are suffering from weevil infestation. We live on the south coast NSW and got them from an area near Gosford. The other three are locals and so far seem unaffected. I'm guessing we've imported the weevils with the palms.

The weevils are ugly, grey and hard. They look dead and dried up and only move their legs when you press them.

We have tried spraying them with a systemic product recommended by a so-called expert but that scorched the new fronds. It did seem to knock the adult weevils off though, but I don't want to risk the new fronds again. This year the exact same thing is happening: the fronds look pretty sad and start to droop where the grubs are boring their way through. I know if we don't stop them the palms will end up without any fronds and could die.

Has anyone else had this problem, and if so, what did you do about it? Did it work?

I had contacted the botanical trust but they thought it was a phosphorus thing, so we have been feeding them all year, which made them look better but hasn't stopped the borers coming back.