Help, cross breeding hibiscus?

[Desirai]

This is my first serious year of gardening. I've always kept houseplants, but this year I began growing everything I could find.

This coming year of 2012, I want to start learning hybridization, cross pollinating and grafting.

I've decided to start with hibiscus, simply because I already have 2 growing in my yard.

However.... I need help.

One hibiscus is known as confederate rose and/or rosemallow. The other one is a pink rose of Sharon.

Can these 2 plants cross breed at all? either by grafting or swapping pollens?

If I buy other hibiscus, which ones can I get that CAN cross breed?

Personally I don't like the flowers on these, I much prefer the huge single-petal flowers that other hibiscus have. these have double layers of petals. (does that make sense)

Basically long story short, how do I know what types of hibiscus can cross breed?