I started doing a lot of container gardening about ten years ago and it has gone from a pastime to a passion that occupies a lot of gardening time and garden real estate. We live on a piece of property that is basically nothing but a glacial rock pile so anything that gets planted here has to have major rock excavation done first. As I progressed from 12" pots to 18" and on up I realized that there isn't anything much you can't grow in a container and eureka! you don't have to dig rocks out first.
The tropical border began just as a regular collection of containers with annuals but expanded as I started collecting tropical and temperennials. What started as a 10' x 10' area in the corner of the front yard is now a 12' x 30' border that houses my largest tropicals. I normally have 45 to 50 containers in this one area each year. The old gentleman of the border is an eight year old specimen of Brugmansia 'Charles Grimaldi'. Not anything special where they are zone hardy but a great old friend to me that has to get severely pruned and shoved into a dark basement over the winter. By Autust it normally pushes out 300 plus blossoms at a time and is a show stopper here in Zone 5. Of course it had to have company so I added Ensete maurelii and lots of different colocasias, acalyphas and cupheas, etc. I also have a four year old Alocasia portodora that will probably be pushing 8' by the end of summer. They are a lot of work but what fun to have a tropical oasis here in New Hampshire.