Last Flourish

We rescued this rhododendron from a  friend's garden a few years ago, when she had to move. There it had grown well but never flowered. 

Here it has produced lovely blooms each spring, but the leaves then drop and do not replace themselves.  It is beginning to look very sad. 

I don't know what to do to help it - I fear moving it might just finish it off.  Feeding and mulching don't seem to make any impact. 

I think it is probably quite old, so perhaps it is just reaching the end of its natural span. So we are just enjoying it while we can.