How Can Cactus Plants Live in the Desert?
Cactus plants have many adaptations that allow them to live in dry areas; these adaptations let the plant collect water efficiently, store it for long periods of time, and conserve it by minimizing water loss from evaporation.
Cactus plants may not get much moisture where they grow, but they make the most of what moisture they do get. The thrifty cactus plant has long roots that grow near the surface of the ground.
They soak up water when a desert rain falls. Cacti have a thick, hard-walled, succulent stem which are photosynthetic, green, and fleshy. The inside of the stem is either spongy or hollow (depending on the cactus). A thick, waxy coating keeps the water inside the cactus from evaporating.
The spongy inside parts of the cactus store a great deal of water for use during dry periods, while the plant’s thick, waxy skin protects the liquid supply in the dry atmosphere.
A cactus plant has few leaves, sometimes none; it has sharp spines which do not lose moisture by restricting air flow near the cactus. Their sharpness also helps keep away thirsty desert animals.