Hi BNutters, I started to reply Weds, when this thread was only one or two posts long, got distracted, came back today, and it has expanded to 50 posts. Granted, mostly about knotweed. Hopefully I can help.
There are several styles of "Bamboo Bonsai", using true bamboo species. Bamboo is a group of grasses, with 1bout 1400 different species from at least 115 genera. Majority are tropical or sub-tropical, but some 50 or more can be found in areas cold enough for the ground to freeze in winter. Kudos to
@Michael P you found my 2014 thread on Internet Bonsai Club, under my full name, Leo Schordje. Unfortunately "Link Rot" has made the photos unavailable. One of the reasons I no longer post on IBC, is that the site doesn't host photos. As I changed ISP's link rot sets in. Here, because BNut does host photos, an older post has better "shelf life" without as much "Link Rot".
So I will copy and paste parts of that old post, if I can find the photos I used, to revive the post. And I will add newer thoughts. Definition: Culm = "Cane", proper term for a stem in grasses is culm, has to do with the structure. Culms in bamboo are normally hollow, divided into segments, with a partition separating segments.
Several styles of growing bamboo for bonsai. First, and least complicated is "kusamono" style, where you make no effort to change the natural proportions of the bamboo, beyond keeping it in a smaller container. Here the leaves and culm internode traits will be normal size. This is "specimen" growing, where you try for slow, but very healthy growth. Prune away any individual culm that is not attractive. Just as kusamono with flowering herbs and grasses, you are not really doing much active intervention to dwarf the plant. Just well controlled, nicely arranged growth. Favorite bamboos for this type of kusamono are from the genus Pleioblastus, notably P. distichus, fortunei, humilis, pygmaea, and viridistriata, are the naturally dwarf and frequently used for bonsai. Also Sasaella masamuneana albovariegata is a choice dwarf variegated. The Pleioblastus and Sasaella are both "runners", and rely on the container to confine the root system. The underground rhizome might have internodes with culms 6 inches or more apart, but because of winding around in the container, the culms will appear to be very close together. The following examples are all less than 8 inches tall, my photos from August 2014 MBS show at CBG. The first is Pleioblastus distichus by "Mike", I neglected the rest of the name. Second is Pleioblastus fortunei by Steve Jetzer, the third is an example of letting the rhizome reach out beyond the container, Pleioblastus distichus or possibly P. pygmaea, by Mark Fields.
This is the most common style of growing bamboo for bonsai, as smaller kusamono type plantings. There is a subset of kusamono, where the kusamono becomes the focal point of the display. Sanyasou is the name for this style of kusamono. Again, there is no real effort to change the length of the internodes or dwarf leaf size of the bamboo. Next photo is from Michael Hagedorn's blog, followed by a photo of 40 inch tall 'Moso' from the Omiya Bonsai Museum.
Again in the above examples, this is normal growth for a confined root system. Using roughly the same growing techniques bamboo can be used for Penjin style plantings. The first with the panda ornament is labelled as being Pleioblastus humilis, but the growth habit suggests it might actually be Bambusa multiplex 'Riveriorum' or 'Fernleaf Stripe Stem' congested leaf dwarf forms of Bambusa multiplex. The second is a penjing by Qingquan Zhao, and again is likely a dwarf cultivar of Bambusa multiplex
I need to take a break, I'll follow up with more comments about the technique outlined by Naka.
. Is not Moso a timber or larger type bamboo?
