What are the best practices for cleaning algae or moss from wood-plastic composite (WPC) sculptures?

Wood-plastic composite (WPC) sculptures are a beautiful addition to any garden or outdoor space, blending the natural look of wood with the durability of plastic. However, exposure to moisture and shade can lead to the growth of algae and moss, which can make surfaces slippery and detract from the sculpture's appearance. Proper cleaning is essential to maintain both the beauty and structural integrity of your WPC art. Here are the best practices to do it safely and effectively.

The first step is regular, preventative maintenance. A simple weekly rinse with a garden hose can prevent organic matter from taking hold. For established growth, create a gentle cleaning solution. A mixture of white vinegar and warm water is highly effective for light algae. For more stubborn growth, a solution of oxygen bleach (which is safer than chlorine bleach for composites and plants) and water is recommended. Always avoid harsh chemicals, abrasive cleaners, or steel wool, as these can scratch and permanently damage the WPC surface.

Apply your chosen solution with a soft-bristled brush or a sponge, working in a circular motion. Allow the solution to sit on the surface for 10-15 minutes to break down the organic material but do not let it dry completely. After scrubbing, thoroughly rinse all cleaning residues away with low-pressure water. A pressure washer can be used, but it must be on a very low, wide-fan setting and held at least 12 inches from the surface to avoid etching the material.

For ultimate protection, consider applying a specialized WPC sealant after cleaning and allowing the sculpture to dry completely. This creates a protective barrier that repels water and inhibits future growth of algae and moss. By following these practices, you can ensure your WPC sculptures remain a stunning and safe feature in your landscape for years to come.