Hi! I am planning to put running bamboo in a location next to block wall but can't figure out if I really need a barrier for it. Here's the layout...My property is 6 feet LOWER than my neighbor's property and a 6 foot block retaining wall separates us. This block wall holds back my neighbors entire back yard (it has major earthquake retrofits so quite substantial.) It also has a very thick footing about 2 feet deep which is below my soil level.

I want to plant the bamboo right next to that wall so the way I figure it, I have 2 feet of poured cement foundation on the neighbor boundary that could act as a barrier. Now the question is, will rhizomes decide to dive down 2 feet and then climb up 6 feet to pop up on my neighbors level?

I feel like that's quite a trip to make but it sounds like bamboo is very clever so I'd love to know what you all think. I could certainly put a barrier in but don't want to if it's overkill. Also, I see that most barrier recommendation are for 24" anyway so wouldn't the wall foundation do the trick?

Thanks!!