Question
Hi, I collect different types of hibiscus plants, some hardy, some tropical and I have a question. Can all hibiscus plants be hybridized, whether they are say, rose of sharons, hardy types, tropical, or even such plants as hollyhocks. Can they all be interbred or cross polinated to result in new types of plants? Thanks for your help.

Answer
Hi Alan,
Thanx for your question.  I don't think you can make the crosses.  Hardy (H. moscheutos) and tropical hibiscus (H. rosa-sinensis) are in the same genus but different species and I don't think the species cross.  Rose of Sharon is also a different species (H. syriacus) and I don't think it crosses either.  Hollyhocks are in a completely different genus and species (Alcea rosea).  I'm not an expert in genetics but I do not believe any of these will cross successfully.  There is not harm in experimenting though.  I hope this helps.
Tom