Thanks all, despite its frustrating growth habit, I am very happy with it. It provides flowers in the greenhouse when virtually nothing else is blooming. It is showing signs that it might be increasing, so I am hoping that there will be two spikes next year.
Rick, the old growth starts to die back shortly after the blooms have faded. It has started a new growth already, but it takes about two years to mature the new hand, so that as the new growth is mature, the old has disappeared. It only ever has three growths, a new, a near mature and a blooming/old. I am going to try and set a pod on it this year, not for the seed, but in the hope that if the pod is maturing for a year, it will delay the growth dying back? Don't know if it will work, but it should be worth the try (and besides having a flask or two of this shouldn't be too much of a hardship)
Hopefully i will get one this year. 
