A damp cloth or sponge should be used to clean the planters. If required a simple detergent can be used. The coating has a high life expectancy similar to that of a car’s bodywork. If the planters are cleaned regularly, they will retain their appearance even after a long period of use.
DO NOT use scouring cleaners or the scouring side of a sponge or similar. The use of these can lead to surface damage, wich in combination with weather can eventually lead to corrosion.
In addition, cleaning in the nearby surrounding of the planter with aggressive and/or acid detergents may affect the surface of the planter.