Miracle-Gro Enriched Potting Mix Miracle-Gro Potting Mix is a lightweight, soiless mixture that not only allows for aeration and water retention, but also contains all the ingredients and nutrients vital to container plant growth. Miracle-Gro is formulated with a blend of composted bark fines and sphagnum peat moss to provide optimal drainage, high amounts horticultural-grade perlite to maintain maximum airflow to the roots and a wetting agent to ensure the even dispersion of water throughout the soil. Lastly, and most importantly Miracle-Gro Potting Mix contains Miracle-Gro Plant Food to get plants off to a fast and vigorous start. Miracle-Gro Potting Mix is available in a variety of sizes 10-quart, 16-quart, 1 cubic foot and 2 cubic feet bags.