Choose a wire basket. Any shape or size will do.
Line your container with a reasonably thick layer of moss and add a plastic liner.
Add a little SOIL on the bottom and begin popping in your preferred plants.
I used a 1 gallon pot of early blooming heather in the middle, some Bacopa and a 6″Campanula on the ends…..
and then threw in 2 – 4″ zonal geraniums for good measure!