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If you prefer a more economical and environmentally friendly approach to commercial products like Wet and Forget, several home-based alternatives have been recommended by extension services and university resources. These methods are particularly effective in shaded areas where green growth—often algae or mildew—thrives on decks and home exteriors.

Natural Cleaning Agents

Hot Water: One of the simplest approaches is using boiling or very hot water to disrupt and remove algae and mildew. Hot water can help kill many microorganisms that contribute to green growth, though care must be taken to avoid injury or damage to surfaces that are sensitive to temperature changes.

White Vinegar: A diluted vinegar solution is another effective option. Vinegar’s acidic nature helps break down the biofilm that algae create. It’s gentle on many surfaces but should be tested first in a small area, as prolonged exposure may affect some materials.

Baking Soda: When dissolved in water (occasionally with a touch of hydrogen peroxide), baking soda provides a mild abrasive action that helps scrub off buildup without harsh chemicals.

Lemon Juice: Like vinegar, lemon juice is naturally acidic and can work as a mild disinfectant. Aside from cleaning, it leaves behind a fresh scent.

These ingredients are readily available, cost-effective, and have a lower environmental impact compared to many commercial cleaners.

Mechanical Methods

Scrubbing and Rinsing: In addition to chemical approaches, physically scrubbing the affected surface with a stiff-bristled brush and rinsing with water (often using a pressure washer on a gentle setting) can be highly effective. This method requires a bit of physical labor but reduces reliance on chemical agents.

Combination Methods: Sometimes a combination of these natural agents works best. For example, applying a vinegar solution, letting it sit briefly to work on the biofilm, and then scrubbing with a baking soda paste can yield good results.

Practical Considerations

Surface Sensitivity: Always consider the type of deck or exterior surface. While washing techniques and natural acids are effective against organic growth, they may interact differently with various materials. Testing a small, inconspicuous area first is good practice.

Maintenance: In shaded areas where moisture builds up, repeated cleaning may be necessary. Regular maintenance using these methods can prevent the buildup of green growth, reducing overall labor and expense over time.

Safety: Although these natural ingredients are generally safe, they should still be used with appropriate safety measures such as gloves and eye protection, especially when combining solutions or using boiling water.

Cover and protect any plantings in the area.

These economical and environmentally friendly approaches have been discussed by university extension services, such as the "Green Cleaning Solutions" provided by the Alabama Cooperative Extension System. They offer a wealth of ideas on how everyday household items can be repurposed to tackle common cleaning challenges effectively.

Check out this link:

Green Cleaning Solutions - Alabama Cooperative Extension System