Chinese hibiscus? Marsh mallow is also commonly grown and normally dies down, to grow back from the roots every year.

It's a tropical hibiscus Rosa Sinensis.

I had a very small tropical that got snipped of to about 1/2" by a stupid rabbit early last spring. I was sooooo angry at myself for leaving it in a vulnerable spot - didn't know at the time that rabbits like hibiscus. But I moved it to a safer spot, continued to water it, etc. It has come back stronger than ever - it is sitting in my kitchen window at the moment waiting for warmer weather to return . . .