Sarracenia (American Pitcher Plants) are good container plants. They are carnivorous plants and do not need fertilzer, they catch own. They have beautiful pitchers and have unusual umbrella flowers.
I have a dual love of perennials and container gardens. I have several containers throughout my garden to add more interest and mix annuals in with some perennials as they are easier to do in containers.
I have two containers that I have planted coreopsis in. They have come back two years in a row now much fuller each time. The containers are this blue color that really look great against the yellow of the flowers. I've left these containers out during the winter.
I do have a red jasmine that is the most beautiful flowering perennial I've yet to see. I have it in a large pot that I do have to bring in once it turns cold. The pot is so large that it takes my husband and I to move it, but I believe this is my "pet" plant from my garden.
I have a sago palm in this royal blue container planted with some lush red geraniums as wells as trailing ivy. I just added a white vinca to give it some contrasting color. I have this container in the front yard at a base of a tree that has very dry soil and the only thing growing there is a yucca plant!
I am always on the lookout for pottery on sale or clearance. Don't be afraid to get something with color. I do try and fill the containers with something that will have a pleasing contrast against the color of the container.
I LOVE putting spike plants in my containers to give them some height. I often use ivy or vinca vine to trail over the container. I am experimenting with a trailing geranium this year to see how it does.
I have found that several perennials like containers so don't feel you have to be closed in to just putting annuals in them.
To me, container gardens are a form of art!