One tidbit of information about true bonsai growing:
Bonsai... The millennia-old art form, still going strongly today!
In Japanese, bonsai can be literally translated as 'tray planting' but since originating in Asia, so many centuries ago - it has developed into a whole new form. To begin with, the tree and the pot form a single harmonious unit where the shape, texture and colour of one, compliments the other. Then the tree must be shaped. It is not enough just to plant a tree in a pot and allow nature to take its course - the result would look nothing like a tree and would look very short-lived. Every branch and twig of a bonsai is shaped or eliminated until the chosen image is achieved. From then on, the image is maintained and improved by a constant regime of pruning and trimming.
It is the art of dwarfing trees or plants and developing them into an aesthetically appealing shape by growing, pruning and training them in containers according to prescribed techniques.
If that is the goal of some cannabis growers, to dwarf their pants developing them into an aesthetically appealing shape by growing, pruning and training them in containers, well have at it. But don't expect Christmas tree yields. If someone wants to grow for a hobby and their priority is to make unique sized and shaped plants, then that is what they should do.
But when bonsai growing is performed properly the roots of a bonsai tree will need to be pruned and the tree repotted after the roots have filled the pot/container, having nowhere else to grow. If not repotted and roots trimmed the soil will become packed and dry making it impossible to water and feed effectively.
True bonsai growing is not just growing in tiny containers allowing the plants to become root-bound. True bonsai growing requires a plant to be trimmed/pruned AND the roots also trimmed/pruned so they have room and do not become root-bound.
As I have said many, many times, plants have a 50/50 ratios of above soil growth and below soil growth. There is equal mass/volume below the soil as there is above the soil, though of course in a different form. When roots are not allowed to keep up with above soil growth, or are not as in the case of true bonsai growing trimmed/pruned back as the above soil portion of a plant/tree is and in doing so retaining that 50/50 ratio you end up with plants having problems, various problems, sometimes many problems.