Since my father died two years ago, I'm afraid the garden has gone to pot
(pun intended), and I've only just acquired the bug (OMG another pun).

Seriously though, I've got a very sick Rhododendron and I'm clueless about
what to do.

There's an identical one on the other side of the garden, that's doing
fine, but the sick one looks very wilted, yellow and "burned" (black areas
on the leaves).

I dug it up and checked the soil ... which looked identical to the soil
the other one is flourishing in. The only difference, AFAICT, is that the
sick plant is slightly more exposed ... oh and I did find a few small
white grubs in the soil, although there was no visible sign of the roots
being munched on.

I bought some fertiliser that claims to be specifically for Rhododendrons,
but I suppose it might take a while to have any effect (if it works).

So ... what went wrong, and how can I fix it?

TIA,

-
[H]omer