Answer: Moss in and of itself is not likely to hurt anything, but it is usually a sign that something is out of balance. Possible causes would be overly acidic soil, poor drainage, compacted soil or excessive shade. Since the pH is slightly alkaline, the soil is sandy and so should be well drained, and the lilies would grow best in a sunny location, I am not sure what is causing the moss. Sometimes mosses grow in a seasonal way and disappear once the weather turns warmer and drier. You might want to consult with your county extension if it is truly a problem for you.
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