Bamboo barrier is made of a high density polyethylene plastic. It is 30″ tall and comes in either 60ml or 80ml thick, up to 200 linear feet long. It is installed to a depth of 25″ to 28″ deep with several inches above the soil surface. This exposed lip is critical to keep the rhizomes from jumping over the top as leaf mulch builds up over time. It is best when offset 10″-18″ from the fence or property line to enable access for maintenance. The most common failures of bamboo barrier are when it is installed too deep or too close to a fence. It is practical for narrow areas where root pruning is not feasible, and should be considered secondary to root pruning.
Totally enclosed barrier where the bamboo is surrounded on all sides has the greatest risk of failure or stunted bamboo. Rhizomes tend to be shallow and diffuse across the soil surface, but when confined will become dense and deep. Over time the pressure of rhizomes can cause barrier to split or become overrun. This density can also stunt the height and diameter of the bamboo as it becomes congested and root bound. It can be very difficult to remedy broken barrier situations and often requires total removal or destruction of the bamboo.
A compromise between total enclosure and all sides root pruning is a three sided barrier. The less accessible property line and sides have barrier while the front side is controlled by a pruning trench. This allows some breathing room for the bamboo, and a pressure release valve for the barrier. It enables a screen to be established close to the property line and maintained on the more open side. This is our most common application of barrier.
With either method of barrier installation space considerations are the first priority. While you can grow a fairly tall screen with a 2′ wide bed, the bamboo will be healthier and the barrier viable for longer with 3′-4′. The most risky situation is a 2′ wide bed immediately adjacent to the fence line as it is too narrow and hard to maintain. Practically speaking your screen could end up taking about 3′-5′ of space. Plan for the barrier to be offset by at least 1′ from the fence, the growing bed taking 2′-4′, and the pruning trench about 10″ in front.