Evergreen is a plant that remains green throughout the year. It grows new leaves before shedding the old ones. Many evergreens keep their leaves for several years. The leaves of some of them are tougher and more leathery than those of other plants. Some evergreens, such as the cone-bearing trees, have needle-shaped leaves. These leaves have less surface area than broad, flat leaves and can resist changes in temperature more easily. Many tropical plants are called broadleaf evergreens to distinguish them from needle-leaved ones. Both kinds of leaves contain chlorophyll, the green coloring matter used by plants to make food.