The Rhizome Clump
A bamboo plant begins with a single culm, or stem. As the bamboo grows, it develops more rhizomes. All of these are a single plant, however, rather than a collection of plants. Each culm on a bamboo grove is identical to its companions. It takes several years for the root mass to mature, but once it does, the grove can spread very fast.
Propagating with Rhizomes
Since bamboo may not bloom for many decades, it’s more often propagated with rhizomes. Here’s how:
- Dig up the entire plant and drive a sharp shovel through the mass to divide it or cut off individual rhizomes.
- Select the rhizomes you want; immediately plunge into water.
- Replant rhizomes at the same level in new pots or a bed.
- Water in well and shade for several weeks.
Bamboo Growing Seasons
Bamboo has two distinct growing seasons. In early spring to summer, the plant puts all its energy into culms. Each culm springs from the ground at full diameter and grows to its mature height in about 60 days. Beginning in late summer, the plant shifts into rhizome development, which continues into the late fall. In winter, bamboo is semi-dormant.
Running Bamboo Rhizomes
Running bamboo is aptly named. These varieties send horizontal stolons out from the mother plant. Multiple culms grow along the stolon in the same way that Bermuda grass takes over a garden or lawn. A species of bamboo called Phyllostachys is the fastest-growing plant in the world, with growth rates as high as several feet a day.
Clumping Bamboo Rhizomes
Clumping bamboo doesn’t grow or spread as fast as running bamboo, because the rhizomes are different. Their growth habit is more like that of an iris, in which the individual rhizomes grow up around the perimeter of the mother plant. However, these bamboo culms have also attained their mature diameter when they arise from the ground and reach their mature height in about two months.
Controlling clumping bamboo is relatively easy because you’re dealing with single rhizomes. Drive a shovel into the clump, pry up the excess rhizomes and burn or replant them. With running bamboo, it’s better to start with a barrier around the plant. You’ll still have to root-prune, but the barrier keeps the bamboo from spreading so fast it becomes invasive.