There are many different types of potting mix, but they can broadly be divided into two categories: soil mixes and soilless mixes. Soil mixes contain a combination of peat moss, compost, sand, and perlite or vermiculite. This type of mix is ideal for plants that require good drainage, such as succulents and cacti. Soilless mixes, on the other hand, do not contain any soil. Instead, they are made up of peat moss, perlite or vermiculite, and sometimes coco coir. These mixes are ideal for plants that prefer high humidity, such as ferns and African violets.