How to prevent algae growth on granite outdoor tree boxes in humid climates?

Algae growth on granite outdoor tree boxes in humid climates can be unsightly and slippery, posing a safety hazard. Fortunately, there are several effective ways to prevent this issue.

1. Regular Cleaning: Wash the granite surface with a mixture of water and mild detergent or a vinegar solution (1:1 ratio) every few weeks to remove early algae buildup.

2. Use Algae-Resistant Sealants: Apply a high-quality, penetrating granite sealant designed to resist algae and moisture. Reapply annually for best results.

3. Improve Drainage: Ensure proper drainage around the tree box to prevent water accumulation, which promotes algae growth.

4. Trim Overhanging Foliage: Reduce shade and moisture by trimming nearby plants or trees to allow more sunlight and airflow.

5. Natural Algae Inhibitors: Sprinkle baking soda or diluted hydrogen peroxide (3%) on affected areas to deter algae without harming plants.

By following these steps, you can maintain the beauty and safety of your granite tree boxes in humid conditions.