Despite the reputation of bamboos being rampant, vigorous growers you will often find that Black bamboos can take quite a while to establish, and tend to be slightly fussy as young plants. They dislike dry, poor soils or soils that sit too wet. They enjoy the addition of plenty of rich, organic matter. Bamboos also need a fairly sheltered site as the foliage can easily become wind burnt. If the plants are being grown in containers then consider re-potting them using John Innes No. 3 and mix in some well rotted manure or other organic matter. The main problem is that until bamboos are fully mature, and completely settled into their environment they will not put up black canes. If they have had a setback in their growth or if they get too dry in summer then this will also delay black cane production. The black canes that have grown up are much sturdier than the young growth and look quite different, being taller and more robust. They will not be black immediately but gradually turn this colour, so it is important not to prune these canes out because they look green!