What kills moss on a roof naturally?

What kills moss on a roof naturally includes several environmentally friendly options that avoid harsh chlorine bleach. One of the most effective natural methods is zinc or copper, as rain washing over zinc strips or copper strips installed near the ridge creates metal ions that naturally inhibit and kill moss, algae, and lichen without chemicals. Potassium salts of fatty acids, found in products like Safer Brand Moss Killer, are considered natural and biodegradable and kill moss by penetrating cell walls. White vinegar diluted heavily with water can kill small patches of moss due to acetic acid, though it must be used cautiously as concentrated vinegar can damage shingles and metal flashing. Baking soda, sodium bicarbonate, sprinkled on moss can desiccate it and change pH to kill it, though it requires reapplication. Sunlight and improved air circulation are natural moss killers, so trimming overhanging branches to allow more sun and wind to dry the roof helps prevent growth. Physical removal after killing is best done gently with a soft broom after moss dies. The most natural long-term approach is prevention through zinc strips, as they provide continuous natural protection with each rain. Avoid pressure washing, which damages shingles even though it removes moss quickly. For best natural results, apply potassium salts or zinc sulfate in late spring and allow rain to wash dead moss away gradually.