Desert plants have adapted to the extreme heat and overly dry desert climate. Their physical appearance, including prickly spines on their foliage and fruits, have also adapted to withstand their environment. Other adaptations that have helped them to survive the arid desert is their ability to collect and store water within the structure of their foliage and stems. This ability to reduce water loss is a beneficial trait that plays an important factor in why these stunning plants can survive among the dry desert landscapes.
The saguaro cactus is the largest cactus in the United States. It begins its life in the shelter of a bush or tree, which provides a shaded habitat. The saguaro grows very slowly, about one inch every year. It can grow up to 60 feet in height, and many develop arms shooting out from the central stem. It is estimated that saguaros can live as long as 200 years. Like most cacti, the flower buds begin to emerge near the tip of the cactus. As many as 4,000 seeds are produced from a single fruit. The saguaro cactus flowers can only be fertilized by cross pollination, which is usually done by bees.
Prickly Pear Cactus
Prickly pear cacti have large spines, which are modified leaves, on the stems. They range in height from one foot to 15 feet. Some prickly pears have long spines, while others have short and dense spines. In the spring their flower blooms range in color from pink to yellow. They have tough wax-coated green pads that retain moisture during long periods of drought. As the pads age, they change their shape and resemble tree trunks. The pads and fruit are also rich in vitamins and minerals. The seeds and fruit are red, but watch out for the prickly spines which cover the fruit, a trait developed over time to ensure survival.
There are many types of agave plants, the most common being the lechuguilla plant. With its long sword-like leaves and saw-like edges, the tips end at a very sharp point. This succulent also produces purple and yellow flowers which don't begin to bloom until the plant is three to five years old. It prefers alkaline and limestone soils. Another desert succulent is the candelilla plant. A member of the spurge family, these plants are used to produce wax--their branches have a thick waxy coating.