The cactus family (Cactaceae) is one of the most striking, distinctive, diversified and specialized groups in the plant kingdom. It includes about 2,000 species, and all of them are perennial. Cacti belong to a larger group of plants call succulents and all succulents have a specialized feature that enables them to survive drought or lack of light due to their water holding capacity. Contrary to popular beliefs, cacti do not grow in deserts, but in arid semi-deserts. In some of the habitats cacti may not see rainfall for years, but usually the ground is very rich in minerals. All cacti come from North & South America though later spread to the Continent and other parts of the world. Some of the common cacti in the USA include the barrel, prickly pear, organ pipe, cholla, and saguaro cacti.
Cacti are a group of plants which are not only easy to grow, but also offer a variety of shapes, color and form. They can be grown in any sunny, well-drained area. They require little maintenance. They make excellent houseplants and many hardy varieties may be grown outside.
Some cactus and succulent types can be used as pot plants. These include Aloe Vera, crassulas, Echeverias, peperomias and kalanchoe.
Larger-growing cactus and succulent plants make dramatic floor plants with heights from 3 to 10 feet or more. These include Cereus peruvianus, Yucca elephantipes, Euphorbias, ponytail palm or bottle palm.
Certain parts of the cactus are edible too. In April and May, cactus plants make new growth. The new growth are not new leaves but stems. Leaves are about 1/2 inch long and the diameter of a pencil lead. They fall off in a few weeks, before the new stem or pad fully expands. The leaf scar is located at an areole from which the spines begin to emerge after the leaf falls. The areole is also capable of sprouting a new stem.
Almost all cactus will flower. However the flowering cycle differs from one cactus to another. Some may flower when exposed to sun for a prolonged period in room environment. Some by sudden supply of water after a long period of dry environment which stimulate its flowering cycle. Besides, temperature change (+/- 10°C) is important to trigger the flowering process in most cases. Usually tiny (depends on the cactus type) seedlings may be found after the flower dried up and the purpose of flower is to give birth to new life.
Some cactus sap has a narcotic effect and has been used in religious ceremonies. The prickly pear (fruit of cactus) are more familiar to most people where such fruit is grown for export. These prickly pears are undoubtedly sweet and delicious. Some species that are widely cultivated for their fruits are Opuntia ficus-indica, Opuntia streptacantha, Opuntia tuna and Opuntia cardona. Many cacti are also used as building materials and as hedges.
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