As I said in another thread I'm trying to propagate a Bamboo by growing these late culms through a pot. The pot was placed above the shoot just as it emerged from the soil. It is grow through a water hole. I piled a little mulch against the side of the pot so that the new shoot was not exposed to air until it broke the surface of the compost in the pot.It seems to be working out so far. There should be a single culm divsion with dormant rhizome buds in the pot, with a little luck it may even start a new rhizome before we get cold weather. There is lass Perlite in the pot than appears on the surface , but it's still a pretty airy mix.

I did a similar test, but I fed a roaming rhizome through a drain hole at the bottom of a pot. I left it for the summer, and recently found that the rhizome grew right through it and out the other side!

This is a culm that I directed through a drainage hole, it should develope rhizomes . I'll check it's root growth and such come Spring.

Perhaps it is obvious - it was not so to me - but I experimented with some pot-escaped rhizomes that had started to branch at the tips but were still sheath covered lower down. It looks like none of these developed any roots, so one must catch them quite early for this to be more reliable.

Brad I agree, this culm was less than an inch above the soil when I sent it into the pot. I'll check for roots and rhizomes before I cut the base. If it has not made roots or a rhizome inside the pot I can back cut under the compost outside the pot as far as I need to and then cut the pot away.It's just an experiment there are one or two more points on the plant I can take a division from. I have a small Semiarundinaria ' Red Fall' that has made a small plant coming out of a drainage hole, I'll be cutting the pot away from the plant come Spring. For once I have a lot of spare pots so cutting a few apart for experiments is not a problem .
Best Wishes
Steve

My guess is that yours worked, I got to all of mine too late it seems so now I have some pots with culms coming out of each drain hole.