Great links! Thanks, Jean. Now my ignorance of them is less comprehensive.
Sounds like "DON'T overwater, use little or no fertilizer and re-pot every 2 years".
When I see "re-pot", I think "do some root pruning and remove as much old mix as possible before replacing it with new, well-draining soilless mix". But it was pointed out to me recently that not all plants like or want root-pruning.
But it also sounds like they naturally drop lower leaves, and need periodic, serious stem-pruning if you want them to be bushy or less leggy.
It just occurred to me that one generic answer for "what's wrong with my potted ZYZ plant?" could always be "It's growing in a container and not many plants evolved to be happy in a small, plastic pot with no real through-drainage".
How can you make a potted plant feel like it's growing in the earth and not a tin can? Frequently give it fresh soil. One quick partial fix is giving it a bigger pot (pot UP) until that's impractical. Then you have to root-prune, remove old soil from the roots, and re-pot with well-draining, well-aerated, relatively coarse mix.
