Hybiscus-when and how to divide

First, how do you spell "hybiscus". I don't know the correct spelling!

I live outside Buffalo, NY and have had three huge hybiscus plants for 
about 4 years. Cut them down to abt 6 inches after the first good frost. 
They come back up from the ground each year. They are slow growers at 
first, so don't give up. Just leave them alone and in August, Sept. you 
will have beautiful blooms. Can't help with the magnolia tree.

I want to know when to divide them. Want to spread around the beautiful 
dinner plate sized blooms. ANY IDEAS?
Sarah

summerlady wrote:

> I don't live in Florida, I live in New Jersey... but I want to plant
some
> hibiscus and a magnolia tree at my house at the beach.  Any advice on
the
> planting and care would be appreciated.
>