@Forsoothe! As an horticulturist I'm interested to find out the origin of your claim too. Also, I understand the frustration when people approach the art of bonsai with no apparent basic plantmanship knowledge (not a dig at you
@Lunarayve, it happens), but this is not the first time I read an unnecessarily dry response from you. Why? You come across as condescending and I was under the impression this forum was open to anybody, not just "masterpieces".
Dry
humor. Sorry I didn't make you smile, but you can't please everyone with a response. Wisteria are difficult to make bloom and a greenhorn should be advised early in the game in order to avoid that which drives people away from bonsai in droves: failure of ~"experts" (perhaps the most loose term in the English language) from telling them not to expect flowering until many years in the future along with rampant growth that is hard to "style". The ~"experts" have a tendency to be critical of bad news regardless of how true or important it is, so it is left to people like me to butt in and tell them the awful truth. Wisteria seedlings in the ground often, -most often, do not bloom for twenty years, and it takes sever root pruning and/or limited root space like being trapped between two paved areas, to make the plant rootbound and begin blooming, otherwise the roots run wildly long. Once they bloom, the carry on, so
standard advice is don't buy one unless
you see it in bloom. Starting a Wisteria from seed is exactly the wrong way to achieve anything resembling positive feedback, feedback which is absolutely necessary for a reasonable person to continue the art and science of bonsai.
It gets worse. Cercis canadensis are also cautionary bonsai, too. They germinate well, but take a long time to flower and are subject to lots of pathogens and are often a short lived tree. While beautiful, they are less common than Wisteria in bonsai for a reason. Outside of that, nobody offered good alternatives for a beginner to get some more immediate
positive feedback from self-planted seeds. Let's see how long this takes! There are always Mulberry and Elm in early summer and Japanese Maples, Amur Maple, Crabapples, various Oak and Dogwood, and Boxwood planted in landscapes that are close enough to foot traffic to acquire seeds from in September. 37 words missing from the above 9 responses. Citrus can be planted from the pips in the next one you eat and make nice houseplants. Easy, peasy.