I live in a residential neighborhood near Sacramento.

I have a new retaining wall built from cement block that has been filled with concrete and rebar. The wall is 3' high and about 25' long.

The wall was built at grade level and sits 18" from my fence. My neighbor (on the other side of the fence) has a retaining wall of the same height that was built from large concrete wall blocks (16"x10"x8"). His wall is also about 18" from the fence.

The fence is old and about to fall down. We will replace it in a few months. When we replace the fence we will fill the space between the walls with soil creating a 25' long x 3' tall planter.

I would love to plant some bamboo here and the neighbor is open to the idea.

I would like something that we could maintain at 15 to 20 feet tall. I prefer more tropical looking plants (we have 8 queen palms and a 40' high mexican palm) so something with big tropical looking leaves would be great.

Any ideas are welcome as well as warnings and things to avoid.

Thanks!