Bamboo rarely flowers, and it is difficult to get a hold of bamboo seeds. The main way that bamboo groves propagate is through rhizomes. Bamboo plants send out new shoots continually, either in long running trails or in clumps of plants. Once these plants have grown for a season or two, their roots can be cut off and they can be safely transplanted.
Find a bamboo root at the proper time of year. You may either transplant bamboo early enough in the spring that it hasn't grown new leaves yet or in the late fall after it has stopped growing.
Put a layer of river sand in the bottom of a pot. This will ensure good drainage for the bamboo.
Select a clump of bamboo or single plant that has just emerged in the last one or two years; pick one that has three or four healthy looking culms. Cut it apart from the rest of the bamboo grove by digging through the roots with a sharp shovel, saw or chainsaw.
Make a circle about 30 cm deep with a shovel all the way around the clump of bamboo shoots. Gently rock the bamboo back and forth to loosen the roots.
Pull the bamboo out of the ground and immediately put it in the pot. It is crucial that you don't let the bamboo dry out before you plant it. Cover the roots with potting soil. Put a layer of mulch on top of the soil to prevent excess evaporation. Water the bamboo.