My neighbor taught me this trick to clean green algae off siding with 0 effort. Here’s how it works
Green algae on exterior siding can make an otherwise clean home look neglected surprisingly quickly. It tends to appear on shaded, damp areas of the house where moisture lingers and sunlight is limited.
The good news is that you usually do not need hours of aggressive scrubbing or a powerful pressure washer to remove it. A simple cleaning solution, enough contact time, and a gentle rinse can do most of the work for you.
Why Green Algae Grows on Siding
Algae thrives where three things come together:
moisture
shade
organic material such as dust or pollen
North-facing walls, areas behind shrubs, and siding located beneath gutters are especially vulnerable.
Once algae becomes established, rain and humidity can help it spread across larger sections of the wall.
The Easy Cleaning Method
