Kim, I can't comment on question #1 but as to #2...I have cascading double blue petunia. It is gorgeous in baskets or in the ground. I have searched and searched but none seem to set seed. Mine is a hybrid, so I doubt it would come back as the original but I was hoping to plant it to see what would happen. I've found seeds on every other petunia I have but not the double. I guess this doesn't answer your question. I've been beating my brains out on this one. Hope soeone else has an opinion. Those seeds have to come from somewhere as I bought them from catalog last year.

I have never found seed from doubles and some hybrids. I just wonder of doubles don't make seed. hmmm, hope someone knows

I think I have seeds on my supertunia doubles. But I understand they are propagated from cuttings, not seed. Are the seeds sterile?

Also, I have doubles in 14 in. baskets which are supertunias also. About half of those have morphed back to singles. Seems every week I have more and more singles in there.