Why do you think you can bonsai a philodendron??!! Or a trumpet tree? Or a palm, for that matter. I normally tell people to go for it when they ask about unnusual choices, but some things are not bonsai-able, the growth habit is counterproductive or flowers too large (they won't reduce as leaves do), etc. etc. And bonsai call for branches... philodendron branches? Some people have 'bonsai'd' the very odd palm, but they have lots of experience and knowledge - palms are not standard bonsai material by a long shot. I don't want to discourage people trying different things, but a philodendron?

Lucy
There are beautiful purple trumpet tree next to palms all over Florida. The seeds came from one of them.
As far as the house palm and the phil. go if they can be kept small they would be used as companions for tropical bonsai.
I'm sure your not telling me that the ficus and the umbrella palm can't be trained as bonsai so what's the problem.
Ficus, purple trumpet and phil as well as palms are growing together all over Disney world.
Imitating nature is one of the goals of bonsai and the horticulturist at Disney World.
Paul

Hi Paul, I didn't mean my note to be so confrontational (hit send, read later!), but I can't fathom a philo. bonsai. If you can produce one I'd be so happy to see it! The point is that a 'tree' grows a certain way, whether apically dominant or not, and it produces woody branches, etc. etc. but philo's aren't and don't, trumpets (also a vine) would have similar challenges, plus the size of the flowers would call for a very large bonsai for proportion's sake. What the fact that the philo, trumpet and palm live together has to do with bonsai-ing them, I'm not really sure.

Lucy
There is a purple trumpet tree and it is not related to the vine. They are many planted at disney world in FL & disney land in CA. You can google them (purple trumpet tree images)
Philo. and palms will be used as companion plants that is if I can keep them small. I am assuming you have used companion plants in your displays.
good luck