What Causes this Colorful Fall Foliage?

I’ve been getting this question quite a bit the past week. And with good reason! It’s hard for anyone not to notice the incredible colors of yellow, orange, red AND even purple hues when driving around the metroplex.  Typically, the most profound fall foliage is produced in years that have wet growing seasons, followed by less precipitation in fall. There are other factors to consider though.

A Beleafably Amazing Change

Throughout the spring and summer, green leaves have worked helping manufacture and process the foods necessary for the tree’s growth. During photosynthesis, chlorophyll (which gives the leaf its green color) absorbs the energy from sunlight – transforming carbon dioxide and water to carbohydrates, sugars and starch. During the fall and throughout the winter some trees take a break from this process. Cooler weather reduces chlorophyll production, which is partially why we get to enjoy the magnificent show. One of the main reasons we see color changes in fall is due the green pigment (chlorophyll) breaking down, allowing the yellow (xanthophylls) and orange pigments (carotenoids), which are hidden most of the year, to shine through.

There are also other changes that have been taking place as the leaves begin to transition this fall. A cell layer develops where the stem of the leaf is attached to the tree. This tissue gradually severs the leaf and seals the cut. When the leaf is blown off by the wind or falls from its own weight, you’ll even notice a leaf scar. Record fall precipitation may have delayed this process, and in conjunction with cool nights and sunny days, helped provide a little more vivid color show from the leaves that are still hanging on.

Another Reason to Fall for Autumn Colors

Recent cooler temperatures and sunshine likely caused chlorophyll to be destroyed a little faster, revealing more yellows and oranges in the past week and also helping the formation of the red pigments (anthocyanins). Low temperatures above freezing typically favor increased anthocyanin formation, ultimately producing the amazing spectrum of red and purple colors we’ve seen lately!

While weather is definitely a contributor, the shorter daylight and longer overnight hours associated with fall are the main factors that lower chlorophyll production– leading to fall colored foliage in deciduous plants.

Branch Out and Plant Something

If you’re looking to add trees with spectacular fall foliage, now may be the best time to buy because you can actually see and pick out the trees with the best colors. Plus fall is generally the best time to plant trees in Texas and its still not too late!

In the meantime, enjoy the incredible show that Mother Nature is putting on for us this week, as these colors are sure to leaf us as quick as they’ve come! 🍂