Answer: As long as your balcony is sheltered from wind, bamboo would be a good choice. The plant must never dry out, even in winter, and it will need repotting or splitting every other year. Once you have potted it on into the biggest pot you can manage, root pruning in subsequent years will mean you can just put it back in the same pot, with fresh compost. I would use a John Innes No 3 compost with controlled release fertiliser pellets mixed with it. Phyllostachys nigra has wonderful black stems and my favourite for good dense cover is Fargeisa nitida, which can reach 3m - a baby in bamboo terms.
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