Deburring and polishing: Cutting will produce burrs and micro-cracks on the edges, which are prone to accumulating moisture and pollutants and becoming initial corrosion points. Use 200–400 mesh sandpaper to polish the cut edges to remove burrs and smooth the surface, creating conditions for uniform patina formation.
Passivation or patina accelerator application: For the fresh steel substrate exposed by cutting, apply a weathering steel-specific passivation agent or a dilute patina accelerator to the edge area. This accelerates the formation of a stable rust layer on the cut surface, ensuring the edge's corrosion resistance matches the overall flower box and avoiding color differences or loose rust.
Sealing for special environments: In coastal high-salt areas or industrial zones with acidic pollutants, a thin layer of matte transparent glaze can be applied to the cut edges (without covering the entire flower box surface) to enhance local corrosion resistance and prevent rust water from contaminating the soil or plants inside the flower box.
