Potting soil is a mixture used to grow plants, herbs and vegetables in a contained garden environment. The first recorded use of the term is from an 1861 issue of the American Agriculturist.
The most common ingredients used in potting soil are peat moss, composted bark and/or other plant materials, sand, and perlite (for drainage). Some potting soil mixtures contain particles of vermicompost, while other contain vermiculite for water retention. Most commercially available brands of potting soil have their pH fine-tuned with ground limestone, and some contain small amounts of fertilizer and slow-release nutrients. Despite its name, little or no soil is used in potting soil because it is considered too heavy for growing houseplants.