I know the most common method for containing is to install a barrier 28in below ground with 2 inch lip on top, fully enclosed. There’s also a method where you can make a raised bed out of the barrier and keep one side of the bed open and the open side has a rhizome pruning trench/sand backfilled trench) so you can prune any rhizomes that try to escape beyond the trench. I’ve heard that bamboos in fully enclosed barriers eventually become root bound and has the capability of causing the barrier to fail eventually with so much pushing from the rhizomes that have no where to go. How true does that sound? One of my relatives has a huge phyllostachys aureosulcata bed that he installed about 20 years ago and no problems so far. I feel like the open trench method is going to be more of a hassle with constant maintenance.

I currently have a raised open sided barrier of semiarundinaria fastuosa and I plan on redoing the barrier soon. I am just done with all the pruning(3x a year that takes 1.5 hours each) and the possibility of missing a spot and therefore escaping. So I plan on removing the existing barrier and put it a new one but this time fully enclosed and raised 10 inches as it is now. The barrier will be supported by cinder blocks. Another important reason why I’m doing is this is because I didn’t make the barrier deep enough, its only 12 inches underground and 10 in above ground. Yes I cut off about 6-8 inches from the top because I didn’t bacfill the bed all the way.

So bamboo experts, which method would be the best?