It depends entirely on the type of bamboo. Established running bamboo, such as Phyllostachys, is one of the fastest growing plants in the world and can put on 30cm or more in a single day during late spring. Clumping bamboo, such as Fargesia, is far more sedate and grows steadily without racing away.
Knowing which type you have makes all the difference to what you can expect, so here is how bamboo really grows.
New canes shoot up in a single season
Bamboo does not thicken and grow taller year after year like a tree. Each new cane, or culm, emerges from the ground in spring and reaches its full height within a couple of months. It never gets any taller after that. What changes in later years is that the plant sends up more canes, and thicker ones, from the base. So a young plant looks modest at first, then produces taller canes each spring until it reaches its mature height.
Sleep, creep, then leap
Gardeners sum up bamboo's first years as sleep, creep, leap. In year one it settles in and puts its energy into roots, so top growth is slow. By year two or three the root system is established and growth accelerates. Most bamboos reach a useful screening height within three to five years, which makes bamboo one of the best plants for fast screening and privacy.
Running versus clumping speed
- Running bamboo (Phyllostachys) grows fast and spreads outwards on underground rhizomes. Vigorous and excellent for quick screening, but it needs a root barrier to stay in bounds. See our guide on whether bamboo is invasive.
- Clumping bamboo (Fargesia) grows more slowly and stays in a neat clump. Better behaved, and the sensible choice for most gardens. Varieties like Fargesia rufa and Fargesia 'Red Dragon' give height without the worry.
How to get faster, thicker growth
Bamboo is hungry and thirsty while it is growing. To push it along, feed in spring with a high nitrogen or lawn fertiliser, keep it well watered through the growing season, and mulch generously to hold moisture. A well fed clump in good soil will always outpace a dry, starved one. Grasses respond to the same care, so if you like the movement bamboo brings, our ornamental grasses are worth a look too.
Ready to plant? Browse our hardy bamboo plants, including well behaved clumping varieties for screening and structure, and explore the full hardy exotics range to build the rest of the scheme.