Primrose stocks three types of metal plant pots: zinc, stainless and corten steel. Zinc is a recent introduction that has superseded powder coated due to its superior corrosion resistance. Available in nearly limitless colours, the material can survive decades of tough exposure. Stainless and corten are both special types of steel. The former enhanced with chromium will maintain its sheen, while the latter will form a protective layer of rust, producing a gorgeous industrial aesthetic.