I live in zone 6a. My hardy hibiscus is in the ground and every year I cut them back and they come back late spring.

I grow my hibiscus seedlings in pots and sink the pot in the ground to overwinter.

All my hibiscus plants are in mixed perennial beds with average water needs.

i am guessing that cattails mean standing water....from what i can tell hib's don' like their feet wet all the time. they need a lot of water but it needs to drain out as well.

BeesNeeds,
I had all of my hardy hibiscus is pots and last year, left them outside. Although we had a colder than usual winter, all of them were lost. My suggestion is you moderate the cold on your porch and let them go dormant for the winter.

As for the habitat....several mallow varieties enjoy living in standing water like 'cat tails'.

Ed

Hibiscus moscheutos, has a common name, swamp rose-mallow. Any of the common garden selections or hybrids include this and OTHER swamp mallows as the base.

I think that name alone will help with the culture question.

Bees,
Plant the pots in the ground if you can for this winter.
Mulch real good all around the pot, about 3 inches.
If you have a more sheltered location, that is good too.
You have picked the perfect plant to plant in soggy or very moist soil. Yes, they will do well there, on the side of the house where you want them.
You can also grow even more from seeds if you want, you can see how easy they are, grow more next year.
They get bigger every year, so I think you will be happy.

Thanks for all the good advice folks, I feel much more confidant now about my new garden plans!

good luck!