Sacha wrote:
We have a Grevillea on the corner of a well drained, raised bed.
It's been there for many years but now is turning brown and dying off
in patches here and there. They're such good value plants and flower
on and off for such a long time that we're rather sad at the thought
of losing this one. Is anyone familiar with gradual dieback in these?

Many refs on the internet to dieback in Grevilleas. Usual cause is
Phytophthora.

You might get away with heavy pruning; it's worth trying as Grevilleas are
very fast growing.

there may be other causes, of course. Any weedkiller spraying been going on
nearby?

--
Jeff
(cut "thetape" to reply)