Ingredients for Cactus Soil

Sand

• Sand is an essential component of any cactus soil mixture. The North Dakota State University Extension Service recommends mixing one part sand with one part garden soil for cacti. Use coarse builder's sand for best results, or any sand that is gritty and has large particles for maximum drainage.

Organic Matter

• Although most typical garden soils are too high in organic matter for cacti growth, some excessively sandy soils may need additional organic matter. The University of Arizona Cooperative Extension recommends incorporating 25 percent organic compost into sandy soils, which will help the cactus retain water and nutrients.

Pumice or Perlite

• Pumice, or volcanic rock, is a helpful addition, particularly if your soil has a high clay content. Cactuslands recommends combining one part pumice with one part low-peat garden soil. Perlite also has excellent aeration capabilities and can be used as a substitute for pumice.

Crushed Rock

• Add a thin layer of crushed granite or pea gravel to the top of your cactus soil mix. This will help the cactus stay dry around the base, and will also help maintain moisture in the topsoil. A granite or gravel layer also provides more even soil watering and it adds to the overall desert appearance.