Corten Steel Planter as a retaining wall or garden hedge

Recently I helped a friend build a brick patio in front of his new house. The court yard area sloped down towards the front entrance so we had to level the patio area by digging up the dirt and installing an interlocking brick retraining wall. The brick patio and the brick retaining wall was a fairly strait forward installation. One issue that came up was that on each side of the retaining wall we had a sloping fence and exposed soil. Extending the retaining wall on each side would have cost more money and a side retaining wall that is just one or two bricks high would look awkward. So we decided to use the rocks that we dug up in the process of leveling to cover up and hedge the exposed dirt. Then we placed a Corten Steel (also known as weathering steel) planter box on each side to cover up the rocks and give the patio a finished look. The combination of the rocks and extra long Corten planers provide a natural transition for the sloping sides which would have been difficult to achieve with brick or other hedging solutions.