We purchased one single Hardy Hibiscus from the farmer's market last year. It was beautiful with its massive, satellite dish flowers. The seller told us to cut it back in the winter and it would likely come back in the spring.
Boy, did it ever!
It went from one plant with two or three stems last year to who knows how many plants with how many stems this year! We love it! It's like a giant, tropical bush!
I should have pruned it down to just one or two major vines and staked it. As it is, I've been doing everything I can to keep the whole thing somewhat contained to the space that the too-small tomato cage indicates is its "home."