I have bamboo at about two years old. It grew nice and healthy, but recently I noticed its leaves became very big (and ugly). Besides, some of them are turning yellow and brown at their edges. What do you recommend to trim it, and fix the issue with the leaves?
“Lucky Bamboo” is actually a member of the Dracaena family of houseplants. The leaf size your photo shows is typical of those plants as they begin to mature. You can find a good picture here.
Your picture doesn’t show whether you are growing this plant in a bowl of water or in soil. If it is in soil, it is definitely possible to overwater the plant, resulting in root rot, which will cause the yellowing of leaves. Poke your finger in the soil and ensure that it is just barely moist, not wet. Only water when it gets a little drier to the touch. (Seems strange, since some people grow them in a bowl of water, but it’s true!)
In addition, the yellowing and browning may be the result of overfertilization, or of build up of chlorine from tap water. As this helpful article from the University of Arkansas suggests, it might be a good idea to save rainwater for this plant. And only fertilize once or twice a year.
Have you checked for insects? These plants are susceptible to attacks from mealy bugs. You can find the information we provided to another indoor gardener who had that problem here.
Finally, the plant does need good indirect light and must not be under or near a vent, so that the temperature remains constant.
If any leaves are very yellow, brown, or tattered, feel free to remove them. They cannot be restored.