There are more than 1,000 different species of bamboo in the world, from creeping groundcover bamboo plants a few inches tall to species with 12-inch-wide canes that grow to 120 feet tall. The bamboo plant is a large grass. Like other familiar landscape and turf grasses, it spreads by underground runners called rhizomes. More than 200 species can be grown successfully in temperate North American climates.
The botanical purpose of bamboo canes, called culms, is to provide nourishment to the underground rhizomes that spread to form groves of bamboo. Culms have periodic swollen areas called nodes; the space between the nodes is called the internode. The rhizomes from which the culms grow have similar periodic nodes and internodes.
Although bamboo is popularly associated with tropical climates, there are larger, temperate species that require only several hours of direct sun a day. Many species under 20 feet tall do well in partial shade. The culms of temperate species of bamboo may die back in extreme winter cold but usually regenerate in the spring when new foliage appears on culms that appeared to be dead.
A newly planted mother cane will not begin producing multiple culms for about three years. No matter what size it is when it is planted, a mother cane is finished growing in size.
Bamboo shoots growing from the rhizomes expand rapidly in height and diameter for 60 to 90 days after they emerge from the ground; they can grow as much as 4 feet in one day. The new, tender shoots can be broken with the slightest bump. A new shoot does not unfold its branches and leaves until it has reached its full height. After the initial period of rapid growth, bamboo culms stop growing. The canes will grow new foliage every year but will not grow taller or wider; one cane will live for 10 to 15 years.
As the spreading rhizomes get larger in diameter, so do the culms that emerge from them. The culms that emerge each spring grow larger than culms that grew the previous year. This continues until the grove of canes reaches maturity. Larger canes have larger rhizomes and produce more numerous, larger shoots. The first culms to emerge are the smallest in size; the culms on the perimeter of the grove are the largest. As the grove matures the older, smaller plants in the center begin to die off.
Although bamboo is an evergreen plant, it slowly sheds older leaves that form a golden brown carpet on the ground. These leaves provide nutrients and mulch for the spreading rhizomes and increase the reach of the colony. The culms add new leaves each spring just below the dying leaves.