Cactus mixes use coarse drainage amendments and porous ingredients to prevent compaction and move water away from roots. Common components are perlite and horticultural sand; using coarse perlite with larger particles increases airflow through the mix and helps excess water drain quickly from the root zone.
Many cactus mixes are described as pH-balanced or buffered. Typical pH-related items noted include buffered or pH-balanced coco coir and the addition of dolomitic limestone to help stabilize or adjust soil pH.
Use a pot with a drainage hole and follow these basic steps: 1) Fill the pot about one-third full with the cactus mix. 2) Position the plant on the mix and add more mix around the roots to the desired level. 3) Press the mix lightly to secure the plant, leaving a small gap at the top for watering. 4) After planting, water and then allow the soil to dry to the touch between waterings.
Common components include drainage particles (perlite, horticultural sand), moisture-retaining bases (coco coir or sphagnum peat moss), structural ingredients such as aged bark or other forest products, pH adjusters like dolomitic limestone, and added amendments such as plant food or beneficial microbes/fungi.
Some listings are labeled organic or peat-free: a specialty succulent/cactus mix described as “organic and peat-free,” compressed coco coir bricks labeled “100% organic,” and a mix noted as “peat and synthetic additive–free.”