The look and style of corten steel planters covered in warm brown patina is very popular.
While the patina on the planters is loved nearly by all, the rust run off that may stain stone or concrete surfaces that the planters sit on is not desired by many.
When corten steel planters are exposed to rain and moisture the metal oxidizes and forms the protective patina. During this oxidation process the rust particles are carried down by water to the surface that the planters reside on.
The best approach to eliminating the appearance of rust staining when using corten steel planters is to design the planter installation in a manner in which the rust does not run off on to concrete, pavers or patio stone.
In this installation the planters are placed directly on pedestals, and the concrete pavers are placed on the sides of the planters leaving a 1/16” of a gap between the paver and the planter. The rust run off drains down to the subfloor and does not come in contact with the concrete pavers.
Here the planters are installed in a pit and drain onto the soil
In this installation the planters are placed directly on the subfloor around the perimeter of the patio and the decorative rock is added for aesthetics.
In this installation the planters are placed on decorative rock allowing the rust run off to filter down to the soil.
Here a drainage tray is used to contain the rust run off from the corten planter. In installations where the planters are exposed to rain, additional accommodation should be made to channel the water from the tray via a drain hose.