How to Make a Petunia Tower -- Basically, it's a ring of galvanized fencing lined with landscape fabric, then filled with potting soil. The petunias were planted through slits in the landscape fabric. This looks like a pretty easy do-it-yourself project!
For gorgeous containers, use the Thriller/Spiller/Filler method. Choose a taller plant as your thriller, a filler to add around the base and a trailing plant to spill or cascade down the sides. More container garden tips @ themicrogardener.