Why do leaves change color?

This week’s weather question is: why do leaves change color?

Tree leaves are green in the summer and spring because of chlorophyll – which is necessary for trees to produce food.

But there are other colors in a leaf besides green that we don’t see until fall.

Yellow pigments are called xanthophylls, orange pigments – carotenoids and reds and deep purples – anthocyanins. We just don’t see these colors when it’s warmer because the amount of chlorophyll is much higher.

Photo: Chris Largent

In the autumn, when nights get longer and temperatures cooler, trees eventually shut off the chlorophyll to conserve energy. This allows the ‘fall’ colors in the leaves that were previously masked by the green to come out.

And weather plays a significant role in how much orange, red and yellow we see.

The best fall forecast for vibrant fall colors are warm, sunny days, cool (but not freezing) nights and average rainfall.

Fall leaves will reach their peak in Columbus and surrounding areas by the end of this month into early November.


Weather leading up to fall also effects the colors we see.

A warm, wet spring and average summer (not too hot or dry) are ideal for vibrant leaves in the fall.

Too much rain, droughts or freezing temperatures are detrimental for pretty fall colors.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s