I have what an app has identified as Austrocylindropuntia subulata. I've had it for about 25 years, although my mum has always looked after it. It's grown from about an inch high to almost six feet and seems mostly very happy. However, one of the branches has collapsed as shown in the first photo below. I think it first started to droop about a year ago so I used a cane to prop it up hoping that it'd eventually support itself again, but it hasn't helped and since it's grown decently since then it can't support its own weight at all anymore.
Is there anything I can do to help it support itself again?
Is it a sign that the plant has been over-watered, under-watered, over-fed or has the wrong soil? Since the rest of the plant seems fine I assume this is unlikely.
It did suffer badly several years ago when the greenhouse it was in was broken in a heavy storm and the whole plant bent over dramatically, but it's been in a conservatory since and seems to have recovered completely. I believe the scarring on the right branch was due to that.
If there's no way to save the branch, would it be possible to remove it and plant it? Do you have any advice about doing so?
Thank you
