Potting soil provides the nutrients and minerals that a plant needs for proper growth. Matching the correct potting soil to the right plant can create beautiful, healthy gardens whether indoors or out. Different types of potting soil include a variety of common ingredients.
Humus, or mature compost, consists of decayed plant life. This dark brown or black soil holds moisture in the ground. Growing roots can easily break through this nutrient-rich soil.
Sand allows water to drain quickly around the plant. This is ideal for plants that fare poorly in water-logged areas, such as cacti.
Peat moss retains moisture for water-loving plants that require moist roots and a flexible potting soil that easily gives when roots push.
Perlite improves the ability of soil to retain moisture as well as increases soil aeration. Perlite is a common ingredient added to potting soil to encourage root growth.
Limestone regulates the pH of potting soil to create an ideal mix for plants that prefer acidic soil, such as azaleas and rhododendrons.