Alleviating damp, shady conditions and physical removal of moss are natural ways to kill it. Moss grows in yards as a result of moisture, shade and poorly maintained lawns.
The root systems of strong, healthy lawns choke out moss and other weeds. Amending pH levels for optimal lawn grass growth, applying organic fertilizer and properly aerating lawns every two years keep moss levels at bay. Physically removing moss with a hand tool in areas where growth is thick kills moss quickly, and sprinkling baking soda or a solution of 1 ounce of lemon dish soap in 1 quart of water kills moss and makes removal easier. Avoiding overwatering or watering at night deprives moss of the moisture it needs to thrive, and keeping trees and shrub trimmed decreases heavy shade.