Christmas cacti need a soil that is high in organic matter and provides great drainage and aeration. This special mix includes peat moss, pine bark, pumice, worm castings, perlite, lime. Peat moss helps with aeration, reduces compaction, and aids in nutrient and water retention. Perlite is porous so it has ideal water retention and drainage capabilities. It also assists with aeration to roots preventing root rot in plants. Lime is good for pH balance in soil. Worm Castings are an all-natural fertilizer that provides essential nutrients to plants. It contains concentrated nitrates, potassium, magnesium, phosphorus, and calcium. Pumice is an organic material that will help to prevent root rot in plants.