What is a moon garden? Is it a garden that turns into a werewolf after basking in the light of a full moon? Is it a garden that only comes out when the moon glows? Is it a garden full of little weeding martians? Unfortunately, most of the notions surrounding a moon garden's true definition are a bit more glamorous than the garden really is. A moon garden is very simple - it is filled with only white flowers. At night, the flowers appear to "glow" simply because they are white.