Perlite is a type of volcanic glass that is heated and expanded to form a lightweight and porous material. It is often used as a soil additive to improve drainage and aeration, especially for succulents and bonsai trees. Perlite can also reduce the weight of large pots and containers, which can be useful for growing collected trees or pre-bonsai. However, perlite has some drawbacks, such as its lack of nutrient retention, its tendency to float and wash away over time, and its bright white color that may not match the aesthetic of bonsai. Perlite is also a non-renewable resource, although it is widely available and relatively cheap. Perlite is one of the many options for bonsai soil mix, but it is not ideal for every situation. Depending on the type of tree, the climate, and the personal preference of the grower, perlite may or may not be suitable for bonsai. Some alternatives to perlite are pumice, akadama, lava rock, or pine bark. These materials have different properties and advantages that may suit different needs and preferences.