PLANTING & CARE

Pruning & Trimming Bamboo

Pruning bamboo is easy, and usually only needs to be done once a year. But there are some tricks of the trade, and you may not have thought about how a little pruning can create a number of desired aesthetic effects. 

When to prune: Fully grown culms can be cut anytime of year. However, if you are trying to keep your bamboo shorter than it would naturally grow, timing is important. You can actually encourage more leaves on the lower part of the plant by cutting right after a shoot has gained its full height, but before the branches have unfolded from the culm.

Where to cut:  Always cut just above a node if you are pruning to reduce height. If you are thinning canes out entirely (for example, taking out dead, old, small, leaning or misshapen culms), cut as close to the ground as possible. Make the cut straight across, so that there is not a dangerous, sharp point sticking up out of the ground.  

Tools for the job: Sharp hand clippers (and blade sharpener) are your best friend. For larger canes, a pruning hand saw and sometimes heavy-duty loppers are useful. Gloves and eye protection are a good idea when you are working inside a grove, because sometimes branches are hard to see when you are up close and personal. If you are creating a small hedge or maintaining a ground cover bamboo, a hedge trimmer is helpful. A ladder is usually not needed – even a 25 foot tall cane is easy to grab and bend down to trim.

Pruning for Aesthetic Form and Function: 

  • Often thinning a bamboo can transform it from “just another plant” to a stunning beauty.  Take out leaning, crowded or misshapen culms once your bamboo is established. 
  • Thinning to avoid root bound bamboo planted in small spaces can be useful.  Water cannot penetrate a bamboo root ball that has become too dense, which stresses bamboo. You can extend the time a plant is happy in a small space by thinning aggressively once the plant is established. As with any potted plant, ultimately you will need to divide or pot-up into a larger space or container, but thinning aggressively will buy you time.
  • One very simple pruning technique is to “limb-up” each culm, which means cutting off the lower branches to expose the cane. This creates the popular “open grove look” and shows off the unique structural qualities of bamboo.  
  •  If you are looking for a dense screen, encourage thick foliage from the ground up. Don’t “limb up”, but with some species you can shorten the branches. These bamboos actually “ramify”, meaning that they create more leaves on trimmed branches, thereby growing a narrower and denser screen. Ask us for bamboo recommendations.
  • Hedging and limiting height of your screen is easily accomplished. Ideally, there is a bamboo species with the “look” you want, which naturally grows to the height you desire in the environment you live. Sometimes we can get close, but the bamboo will need minor pruning. Even if you want a more formal or stylized hedge, cutting the canes that grow out of bounds need happen only once or twice a year.
  • Dwarf or “ground cover” bamboos often do best by being mowed or hedged in late winter/early spring.  This rids the plant of old, tired leaves and gives room for fresh, abundant new growth.
  • Deeply weeping bamboos can stand nearly upright if their canes are shortened, reducing the weight on each culm. 
  •  A special note about clumping type bamboos: Most clumpers can become extremely dense, and thinning not only improves their appearance, but makes it possible to reach and maintain the inside of a clump over time.