Why Leaves Change Color

Look at trees in autumn. Green leaves turn yellow, red, and orange. Why does this happen? The answer is in the science of plants.

Leaves are green in spring and summer. They have a special chemical inside. It is called chlorophyll. Chlorophyll helps trees make food from sunlight. This process is photosynthesis. Trees need sunlight and green leaves to live.

In autumn, the days get shorter. The weather gets cooler. Trees know winter is coming. They stop making new food. Chlorophyll breaks down and goes away. The green color fades.

When the green color leaves, other colors show up. These colors were inside the leaf all summer. But the green chlorophyll hid them. Yellow and orange pigments appear.

Some trees, like maples, make a new chemical in autumn. This chemical makes red and purple leaves. Sugars stay trapped in the leaves. Bright sun and cool nights create deep red colors.

Soon, the tree drops all its leaves. Bare branches help the tree survive cold winter winds and snow. Without leaves, the tree saves water and energy. In spring, new green leaves will grow again.

What is your favorite autumn leaf color?