Bamboo is actually a woody type of grass that grows primarily in Southeast Asia. Several different varieties exist, and some of them grow very fast, as fast as a foot a day in its short spring growing season. This allows bamboo to replenish itself over the course of about five years, which is why it is hailed as a renewable wood source. Bamboo loves water and continually draws it out of the ground as it grows, to a greater extend than most other plants.
Bamboo Flooring Production
Bamboo flooring is made by taking bamboo and breaking it apart into long fibers--not as small as the individual fibers that are used to make paper but large enough to maintain the bamboo look and texture. These pieces are then combined in a vat with water and boric acid to remove most of the sugars. After this, the strips are glued together to form the boards used for bamboo flooring. These boards are naturally water resistant.
The flooring itself is always protected with sealant, which makes the bamboo even more water resistant while also preventing damage that may be caused by, for example, dropping heavy objects on it. However, water that seeps into the flooring from other places or standing water on the flooring can still be a problem. This water can cause the bamboo to "cup" or curl upward at the edges, especially if combined with heat.
Bamboo floors should be cleaned using regular water. While it may be tempting to add a cleaner to the bucket, most cleaners can actually strip away the water-based sealant on the bamboo floor, wearing it away faster. Warm water is one of the best ways to clean bamboo, with intermittent use of wood floor cleaners designed to add protection to the boards.
Mildew can sometimes be attracted to the bamboo under the right conditions. Mildew is caused by spores that float through the air until they find a moist surface with enough darkness to grow in. Bamboo floors that are properly sealed should not have problems with mold, but worn bamboo floors in humid climates, or floors that are exposed from underneath the house, can be susceptible.