Corten (weathering) steel beds

Corten steel is a chromium-copper alloy that forms a protective rust patina over 6-24 months, then seals itself and stops corroding. The result is a distinctive rust-orange to deep purplish-brown finish that many find architecturally striking. Corten beds last 20+ years and require zero maintenance after the patina forms. The surface rust is non-toxic and actually provides trace micronutrients (iron, manganese, copper) that benefit plant growth. Corten is safe for growing edibles. Brands include Corten steel planter suppliers and custom fabrication shops; expect to pay $200-600+ depending on size. Caveats: rust run-off during the 6-24 month patina development phase will stain concrete, stone, or brick surfaces below the bed, so plan placement accordingly. Corten is significantly heavier than galvanized steel. The bed must have good drainage because constant wetness on interior surfaces (without dry cycles) can accelerate corrosion beyond the protective patina. Plant heat-tolerant species near edges in hot climates.