You've got a good plan and you're not going to have problems. You're just going to be removing runners that go too far. Over time, the plant will send up new culms -- within the space you've defined -- that are the maximum diameter and height for that species in those conditions; the older culms will die out and need to be removed in probably 5-7 years. If you're getting too much growth, the combination of rhizome pruning and taking divisions (which won't be very hard at all) will allow you to maintain control and manage things just fine. With the plan you have and the use of runners, I don't think you'll have some monster rhizome system to worry about. In several years you'll simply have some nice, mature, well-defined clumps of beautiful bamboo.

Kudzu9

You are on the ball this morning Kudzu! A very quick response if I may say so !
Thanks for the reassurance , I will proceed with the plan.

Acercon3-
Good luck. I'd love to see pictures of the planter when it's done...and I'm expecting you to post more photos in 5 years...

Kudzu9,

Sure thing, I will post shots of the planter once it is built and planted. Now I need to pin down the guy I have contracted to do the job! He was supposed to have done this 2 weeks ago. Like most tradesmen around here they are full of promises but need to be led by the nose to the job in hand! I suppose that when there is an abundance of work out there they can call the shots.
I have only become interested in bamboo very recently and have learned much from this forum. I have been inspired to plant a hedge and have phase one already in the ground. The planter will be phase 2 and phase three scheduled for next Spring.

Kudzu9,

I am just finalising details with the guy who is building my planter . I have a question, I initially reckoned on 2 1/2 ft depth for this planter , in your opinion would I get away with making it 2 ft deep ?

I think you'll be ok. I've dug lots of bamboo and I've never found rhizomes deeper than about 15", even on mature timber bamboo. However, I want to make sure I understand your plan: Is this planter going to be on a concrete pad, or will the soil beneath the "good soil" be accessible? The reason I ask is that I think it would be important to have the bottom "open" so that water and nutrients are able to freely move within the subsurface. I made the assumption from your original post that the only cement would be that used to hold the fieldstone perimeter together. Let me know which it is.

kudzu9,

The 'good soil' will be directly on top of granite chips ( which is ground level)and there will be good drainage. Below the granite chips is what we call hardcore, basically crushed concrete etc.
In so far as nutrients are concerned that will be down to me as they will not be available from below.

I think that will work...