Potting mix is a man-made material composed of natural substances, including decomposing bark, peat moss, minerals, and perlite. The main difference between garden soil and potting soil is the addition of topsoil, which makes garden soil heavier. Raised bed soil is a specific mixture of soil formulated for raised garden beds, containing the ideal balance between potting soil and garden soil. Potting mix is too light to be used in raised beds, while garden soil is too heavy. Raised bed soil possesses amazing drainage properties and provides gardeners with well-maintained loose soil that establishes a favorable environment for your plants.