Lucky bamboo plants, which are actually closer to lilies than bamboo, can grow rapidly under the right care and conditions. They're famous for both the positive energy they bring to a space (an ancient Feng Shui staple) and their hardiness. At some point, usually after about a year, lucky bamboo plants will start to outgrow their containers. This condition, called being pot bound or root bound, is remedied by either trimming back your plant's roots or transplanting it to a larger container.
Prepare your new plant's water in advance. Fill a large, open container with tap water or filtered water and let it sit out for a day or so. This helps the chemicals in it to work their way out, which prevents excessive algae growth and root damage.
Hold your bamboo plant in place with one hand while you carefully pour out as much of the water and anchoring medium as you can. Place a colander in the sink first if you plan on reusing the anchoring medium.
Lift out the plant, taking care not to rip, pull or otherwise force the root system out of the container. Gently move the plant from side to side if necessary to loosen the root ball.
Use your fingertips to gently pull some of the roots apart so they're not in a tight ball. Skip this step if it cannot be accomplished without damaging your plant. Examine the roots for general health. Use sharp scissors to trim off any black or mushy roots. Healthy roots should be orange or white. Set the plant aside for a moment.
Thoroughly rinse the rocks or anchoring medium you plan to use to remove any dust, bacteria, algae or other material that may harm your bamboo plant. Rinse out the bamboo plant's new container with plenty of running water. Avoid soaps or detergents.
Place your plant in the new, larger container. Add the anchoring medium to the container, on top of the roots and as far as 1 inch up the stem. Add the room temperature water to your container, as deep as 1 inch up the stem. If it's time to fertilize your lucky bamboo plant, add one to two drops of liquid fertilizer now.
Keep your plant warm, in 70 to 80 degree conditions with an ample supply of indirect sunlight as it adjusts to its new home.