I've had a cordyline(?) in a container for about 4 years, it's the
red/brown ttype. It always seems to have done fairly well, and blades
were about 18" long, but they've been dying off from the outside in,
over the last few weeks.

I'm tending to think I've been over watering it as it tends to get some
whenever neighbouring containers get watered.

it it toast? Any hope of growing it on from the risomes?