3 Basic Potting Soil Ingredients

Sand

• Sand, whether it is coarse, builder or sharp, improves aeration and drainage of potting soil. Sand does not, however, improve water-holding capacity. Do not mix sand with a clay-based soil. Playground sand and coarse river sand are two types of soil that may be used in a potting soil mixture. Playground sand contributes to a loose mix, while coarse river sand allows roots to function more efficiently.

Perlite or Vermiculite

• Perlite promotes good draining in potting soil. The high-fired volcanic rock creates pockets for water passage but allows air to remain. Unlike perlite, vermiculite can hold nutrients, water and air and is sometimes used in place of perlite.

Sphagnum peat moss

• Sphagnum peat moss lends two important qualities to potting soil mix. It provides water-holding capacity while allowing for good aeration. It is important to add sphagnum peat moss in the proper quantity as too much can restrict soil draining.

Potting Soil Recipes

• The three basic potting soil ingredients are the foundation for myriad potting soil recipes. Coarse river sand is one of the primary ingredients in a potting soil recipe for annual plants, for example. Perlite is one of the key ingredients in a potting soil recipe for woody and perennial plants. Playground sand is one of three parts that makes up a potting mixture for alpine plants.