My plants are not mature enough to make much comparison yet, sorry. I just got most of them in the ground this year, and they are small but establishing well at least. The most I have noticed about cultivar differences are all about flower color and some degree of leaf shape or variegation. But not enough info to really post about yet.
What I have noticed is that mature leaves are too tough to be desirable for eating, even if everything else about them would be ideal. Maybe the young leaves would be better? , or the flowers I haven't tried. I'm sure I got my info from Plants For a Future (PFAF), in case you want to check it out, and once they're big enough I might try a few experiments again.
And definitely, I'm talking about Hibiscus syriacus.

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