Quality Steel Planter Boxes

Corten (also called weathering steel) is a steel alloy that forms a stable, adherent rust-like surface when exposed to weather. Unlike standard steel, this oxidized layer acts as a protective coating that slows further corrosion. It's ideal for outdoor planters because it gets better-looking over time and requires no painting, sealing, or coating to stay protected.

During the initial weathering process, corten steel does produce orange-colored runoff as it develops its patina. This can stain concrete, wood, and stone beneath the planter. We recommend placing planters on a material you don't mind staining, elevating them slightly, or using a drip tray during the first season of weathering.

Almost anything. Herbs, vegetables, flowers, small shrubs, and ornamental grasses all do well in steel planters. The heavy walls insulate roots from extreme temperature swings and the drainage keeps soil from becoming waterlogged.

Drainage holes should be drilled before filling with soil. The steel is workable with a standard drill and metal bit. Drill several holes in the bottom — size and number depend on the planter dimensions and what you're growing. We recommend doing this before the patina develops.

No. Corten steel is designed to weather without any coating. Sealing or painting it can actually interfere with the patina process. Leave it as-is and let it weather naturally.

Yes — that's exactly what it's designed for. Corten steel handles freeze-thaw cycles, rain, sun, and snow without deteriorating the way painted or thin-walled planters do.

We offer a wide range of sizes from 12"×12"×12" up to 24"×24"×24" and beyond, with and without an interior shelf. Browse the full product grid above to see all available options and dimensions.