Hi,
It?s either a Borinda or Fargesia, I hope this new genus will stick , the evidence for splitting Fargesia seems quite compelling. I saw this listed at the ABS auction , so someone must be importing these new collections , perhaps it won?t be long before their widely available !
It will be quite hardy as this one was collected at 3500-M in Tibet, two species were introduced from this area Kr 5287 and 5288, these numbers can get quite confusing after a while but the two are very different, the larger and quicker growing one is 5287 which is much darker in culm and leaf. The 5288 is slower growing but the culms have longer necks giving a more open look, it?s also said to be a lighter green( both look the same to me though).
I have both growing here , though they are still young having been in the ground two seasons only, the growth is quite amazing far better than any Phyllostachys growing here. All the cultivated plants from the Keith Rushford collection are yet to mature and show their true potential , the original plants are planted in a university/botanical garden and are said to look stunning, clumps 5/6 foot round and 810 m tall. But have been planted in the outer reaches of the garden in mature woodland without any additional watering , the last I herd the new shoots were being attacked and eaten by squirrels , hopefully there sort this out.
Here?s a Pic of KR 5287- Two seasons from a small division

Bamboo...Please note... This plant is seriously addictive and you may lose interest in other, less rewarding plants!