Was it a new plant then? It could be slow at getting established because of the hot weather we had during this period. As long as it's healthy, just be patient. It'll soon take off!

Bamboos are always slow to establish, and black bamboo is less vigorous than most of them.
Once they have got established though they will start to spread and send out runners and new shoots like nobody's business. Our ordinary clump of green bamboo has sent up complete new canes/stems about 14ft high in a matter of a few weeks.

Yes, mine's doing that, Bertie.

Be very glad it's not growing too fast, like the green kinds.

As Bertie says all Bamboos take quite some time to establish - often several years - and will not make any substantial above-ground growth until they are happy and established below ground with a good root and rhizome system.

Bamboos have an extremely unjustified reputation for being invasive and/or vigorous. The problem comes with planting the wrong plant in the wrong location. It's like planting a Beech tree in your back yard and then being surprised when it reaches 70 feet and leaves no space or light for anything else. That's what they do!

There are over 1500 species of bamboo, the majority of which are not invasive in any way. The most vigorous, running varieties are, of course, also the ones that are easiest to propagate, and it's for that reason that they are the ones most often offered for sale. Some of these are entirely unsuitable for general cultivation and should not be used in a regular sized garden, and I would include almost all of the Phyllostachys species in that.

We grow over 60 species of bamboo including many Phyllostachys, and they are truly massive plants when well established and all have a running rhizome - very impressive in the right setting but soon overwhelming for a regular sized garden.

The best species of bamboo (both ornamentally speaking and also from the point of view of garden use) are tightly clump-forming. They will never spread at all, just slowly increase their clump size. Genera like Fargesia, Thamnocalamus, Drepanostachyum & Himalayacalamus are amongst the best and most beautiful of bamboos. They are trickier and slower to propagate and thus sometimes more expensive to buy, but much better suited for the garden.

SIGH............oh dear, Ilex, you are a very knowledgeable person, but you don't 'alf go on! LOL.....this poor guest only asked about his black bamboo!

( And DON'T take that the wrong way - I'm teasing!!!!)

I know Spritz - I can only apologise!!! the whole Bamboo thing is one of my bugbears is all :-)

LOL.. I 'might' let you off in that case!

(I might well need you to give 'me' some advice at some point, so I mustn't upset you, must I?) ;-))

As another 'windbag', can I just say I find Ilex's info. very useful, especially when so detailed.. Sometimes the detailed answers to questions help inform all of us... you never know who is reading the answers. I find I've learned so much since I started following GOY.

I know - I 'did' say I was teasing, Bertie! ;-)

Sorry SH, I didn't mean to sound pompous, I realised you were just teasing.

:-)))