Why Do Leaves Change Color in the Fall?

It's easy to fall in love with fall; it's arguably the prettiest month of the year. It may be a time for pumpkin spice flavored everything and Black Friday shopping, but despite the incredibly creative endeavors that people produce at this time of year, it doesn't come close to the natural beauty of a forest full of green, yellow, orange, and red leaves. But have you ever wondered why leaves change color in the fall? Let's find out!

What Makes Leaves Change Color in the Fall?

Fall turns a forest into nature's vibrant canvas, but what is the paint? The natural color of leaves is green, principally because of the pigment chlorophyll. Chlorophyll is a molecule that helps plants turn sunshine into energy. However, once fall rolls around, and the sun takes a vacation of sorts, many species of trees have evolved to shed their leaves.

Why Trees Shed Their Leaves in Fall

Why would trees choose to get rid of one of their primary sources of energy? It's a matter of efficiency. Trees need to put energy into their leaves to keep them healthy, which means during the winter when there isn't much sunlight for the leaves to harvest, the tree would be using more energy than the leaves could help create.

Once the balance tips beyond efficiency, trees break down the chlorophyll in their leaves and absorb the pigment back into their bodies. Then the trees lose their leaves for the winter months before regrowing them for spring.

The Process That Makes Leaves Change Color in the Fall

The process of chlorophyll leaving the leaves is what sparks the magnificent color change in leaves. The green pigment saps out of the leaves heading back into the tree's main trunk and branches. This results in other natural pigments like carotenoids and anthocyanins coloring the leaves.

Carotenoids are responsible for the yellow and orange hues that you see on trees and can be found in other common autumnal foods like pumpkins and yellow squash.

Anthocyanin is a pigment that can tint things shades of red to blue and everything in between. Anthocyanins are found in anything from berries and fruits to purple cauliflower.

The fantastic range in color that you get in a single tree during autumn, and sometimes on a single leaf, is due to the tremendous combination of pigments showing up.

While these festive colors technically signal the shedding of leaves which could be considered a sad and somber occurrence, it's really just a period of dormancy, similar to the dormant states animals such as hummingbirds and raccoons enter. Next spring, the trees will grow fresh, bright green new leaves, ready to soak up the sun.

So, now we know why leaves change color in the fall, and one thing's for sure - seeing the beautiful colors develop is one of our favorite things about this season. Browse our Trees Collection to find tree apparel that helps to plant more trees and donates to ecological nonprofits!  

Photo: @hiba.travels