About 5 years ago, Sheridan Cleland of MyPDFscripts wrote the below article on his blog. Soon after, the site disappeared. I wanted to keep the memory alive, because these practices by the studios have not changed. They have only become worse.
Cacti are one of my favorite types of plants to grow inside all year and outside in summer. Unfortunately, the ambient air tends to stay moist during most seasons, a condition which makes cacti unhappy. Cactus potting soil can enhance drainage, increase evaporation and provide the dry conditions that cacti favor.
Place your cactus in the potting soil using gardening gloves. Gently push it just deep enough to allow it to stand up straight. 7. Put the potting soil around the base of the cactus and pat it gently with your hands. 8. Place a layer of gravel or sand on the top of the potting soil around the base of the cactus. 9. Place the cactus in a warm, sunny location where it will get 4 to 6 hours of sunlight each day.