Actually a succulent, not true cactus, the Euphorbia tirucalli needs full sun, well-drained soil, and 50 - 70 deg F. It can grow to 30 ft if not pruned. Always wear gloves and other protection to prevent skin irritatation. . Succulants are plants that have thick, fleshy leaves that store water. Cacti are succulants, but all succulants are not cacti.
Euphorbia tirucalli is possibly toxic to children and pets