Corten steel

Herstera planters are made of Corten steel, a high-performance structural steel characterized by high mechanical resistance and exceptional durability in outdoor environments exposed to atmospheric agents.

Composition and characteristics of Corten
Unlike conventional steel, Corten steel is a special alloy containing copper, chromium, and nickel. This unique composition promotes the natural formation of a protective oxide patina on the surface, which acts as an effective barrier against corrosion, without requiring additional coatings or protective treatments.

Oxidation process and long life
Over time, the oxidation process stabilizes: the protective patina prevents further corrosion and protects the material from degradation. Thanks to this natural mechanism, Herstera Corten steel products guarantee a very long service life, up to 30 years, even in particularly harsh environmental conditions.

Sustainability and timeless aesthetics
Corten steel is a recyclable and paint-free material, making it a more environmentally sustainable choice. Its warm, natural appearance evolves over time, blending harmoniously with its surroundings. Without the need for glazes or artificial finishes, it represents an ideal solution for Herstera's landscaping, urban design, and contemporary architecture projects.

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WARNING
This item is not a toy. Not recommended for use by children under 6 years of age without supervision. Small parts may pose a choking hazard. If the product tips over, it can cause serious, fatal crushing injuries. Sharp edges. Use appropriate gloves during assembly. Some areas of rust may appear due to weather conditions during storage. These do not affect the quality or final appearance of the product. Upon receipt, the products should be unpacked immediately to release any trapped moisture. This product is supplied unoxidized and naturally develops its patina on the outside. For immediate oxidation, a rust accelerator can be used. In the initial stages, Corten steel can release residues that stain nearby surfaces, especially porous ones. The use of protective paint is recommended, particularly on the interior and on exposed surfaces. We do not recommend using Corten steel within 2 km of the coast without paint or sealant. Ensure good drainage without standing water. Do not use expanded clay. Herstera Garden SL is not responsible for damage caused by rust stains.

Rust accelerator

Natural oxidation of Corten steel

The natural oxidation of Corten steel usually takes place over a period of 4 to 12 months , depending on climatic conditions.

To speed up this process, we recommend applying a rust accelerator by following the steps below:

1. Surface preparation: Degrease the metal surface before use. Sanding is recommended for a more uniform finish.
2. Application: Apply the rust accelerator evenly using a roller.
3. Activation: After 2 hours, apply water or an additional coat of accelerator if necessary.
4. Oxidation progression: The process will continue for approximately two weeks. The initial orange color will gradually darken until it reaches the characteristic shade of stable rust. In dry weather, spray the surface with water occasionally.

Additional protection with paint

In projects with intensive irrigation systems or located in areas with heavy rainfall, it is recommended to apply a protective paint , such as Corten+® or Owatrol® , to the inside of the planters.

This protection helps prevent deterioration of Corten steel caused by continued exposure to moisture.

For exterior surfaces, the use of paint is optional and can be chosen based on the desired finish or to avoid any stains on the flooring.