Plants adapt to different climates by modifying their leaves or stems or by shedding their leaves en masse in the fall and going dormant during the winter when there is less water available. They may also have root systems and reproductive strategies that are adapted to the climate.
Succulent plants have several strategies that help them live in climates that are often hot and dry. Their leaves and stems tend to be thick and fleshy because they are used to store water. Some may have tiny or absent leaves, with stems that do the work of photosynthesis. Some of these plants also store water in their roots so that they can die back during prolonged droughts and revive when rain returns.
Plants may also have hairs or spines that cut down on the amount of air around them and reduce water loss by evaporation. Their roots may be shallow in order to take advantage of sparse rainfall or even dew.
Botanists believe deciduous trees shed their leaves in the fall to conserve water. Just before the leaves fall, the tree takes in nutrients from the leaves. Many deciduous trees use their leafless state to blossom in early spring. This makes it easier for any wind to pollinate the flowers.