From Creatures Wikia
The protein-rich berries growing on the tall Bramboo stalks make sweet and nutritious snacks for Norns - if they can reach them! The bramboo stalks themselves thrive in hot, wet environments, and so the lower, rainforest-like level of the Norn Meso is a perfect home for them - however, they are very adaptable and will also grow in most areas of Creatures 3, even the Desert Terrarium!
The colouration of bramboo berries mutates over generations, which can make for a very colourful (or drab) Norn Meso.
If you dislike the colouration of the successful bramboo berries, you can get the Growing Bramboo Vendor which dispenses fertile bramboo berries in all possible colours. Alternatively, you could try setting the tint of the berries with the C3/DS CAOS Codes.
Did you know?
If you don't hatch any creatures, the bramboo plants can evolve to be really short, but if you let some norns in, they will evolve to be tall! (why? because the norns will eat all the berries in their reach, so those that are short will be picked bare, and won't produce more plants!) Also, the flowers of the bramboo plant are one of the few actual DS "flowers" recognized by the game. The Explodonut has the only other flower naturally occuring in DS without adding any agents.
Also, Bramboo has a glitch that occasionally causes it to 'float' above ground, but it will grow as normal, only seemingly out of thin air.