Why Do Leaves Change Color in Autumn?

Summer brings warm weather and long days. Trees use this time to make food. Green leaves do this work. They catch sunlight and use water and air. This process is called photosynthesis.

Green leaves get their color from a special substance. It is called chlorophyll. Trees make a lot of chlorophyll all summer long. This makes the leaves bright green.

Autumn brings cooler weather and shorter days. Trees know winter is coming. They prepare for the cold. Trees stop making new chlorophyll. The old chlorophyll breaks down and fades away.

When the green color goes away, other colors appear. These colors were inside the leaf all along. Yellow and orange pigments hide behind the green in summer. Now they show.

Red and purple colors come from a different process. Trees trap sugars inside the leaves before they fall. These sugars make new red and purple pigments.

Soon, the tree seals the spot where the leaf connects to the branch. The leaf falls to the ground. This helps the tree save water and energy during the cold winter months.

What is your favorite autumn leaf color?