Sun-loving cactus plants are those that appear the way we normally expect a cactus to look. They are native to arid desert regions where they receive direct sunlight for a large portion of the day. In the home, these plants should be placed in a window with a south or west exposure where they will receive direct sunlight for at least a few hours each day.
Succulents are plants that have organs such as leaves, stems or roots that are capable of storing water during the rainy or wet season in order to survive extended periods of drought. All the plants in the cactus family (Opuntiacea = Cactacea) are considered stem succulents. During periods of moisture, the stem swells and then during droughts slowly contracts.Cactus that have ribs are particularly well adapted to this as the ribs fill in and contract like an accordion.
The key to understanding where cacti survive is noting that they are adapted to regions where the environment is limiting and that there is a lack of competition from other vegetation in terms of light, moisture and nutrients. Depending on their habitat, cacti have a variety of survival mechanisms to overcome their harsh environment. In the drier regions, cacti go dormant during the hot dry season and only grow and flower when there is moisture. Sometimes, the desert cacti flower, set seed and then go dormant again over the space of only a few days.
