Why Do Leaves Changes Color in the Fall?

We all enjoy the colors of autumn leaves, delighting in their ephemeral beauty, knowing that all too soon their leaves will drop and winter will be here. Have you ever wondered why leaves change color?

Plant leaves contain pigments that give them their color. The three primary pigments in a plant leaf are chlorophyll (which gives leaves their green color), carotenoids (which provide yellows, oranges and browns) and anthocyanins (responsible for purples and reds). During the growing season, the dominant pigment in most plant leaves is chlorophyll. Plants use chlorophyll in the photosynthesis process. In this amazing process, plants take carbon dioxide from the air, water from their roots, and combine them with sunlight taken in through their leaves to produce glucose (sugar). This is what they do to make their own food.

As summer ends, and sunlight lessens as days begin to get shorter, chlorophyll production slows and eventually stops as plants prepare for winter. When the chlorophyll breaks down, the other colors that have been there all along become visible, and we start to see the change of color. The amount of the various pigments in a leaf are specific to each species of plants, and will also vary from plant to plant within a species. That’s why plants have different colored leaves, and some plants, even of the same kind, are more colorful than others.

Fall color is also influenced by the weather. Temperature and soil moisture are the two main factors. Warm sunny days, followed by cool but not freezing nights, bring out the best color. Too wet or too dry conditions will often result in less dramatic fall color.

Every autumn is different, every autumn is to be appreciated. It has been said that if a person lives 80 years old, they have only had 80 Octobers to appreciate the beauty of the autumn leaves. Take the time to appreciate this special phenomenon.

Just a few of our favorites with spectacular fall color are Triflorum Maple, Paperbark Maple, Serviceberry, Burning Bush, Fothergilla, Itea and Oakleaf Hydrangea.

Autumn is Great for Landscaping

Along with the milder temperatures and beauty of fall comes an excellent opportunity for landscaping for your yard. The cooler weather is a signal for plants to stop growing new shoots and leaves above ground, but not below. Trees and shubs continue to extend their root systems, making fall an ideal time to plant. The cool weather reduces the risk of ‘transplant shock’, or dieback, giving newly installed plants the time to acclimate themselves to their new home and set out new feeder roots before winter arrives. As the soil temperature cools and seasonal rain adds moisture, plants continue to establish themselves. This means that new plantings are less reliant on you (or your irrigation system) for their watering needs when next summer rolls around.

Trees, shrubs, and perennials planted in fall have plenty of time to develop before the wintry weather sets in. When the long, cold winter ends, you will have a new look in your garden and your plants will be ready to embark on a new season of growth.

The fall season is also great for landscaping with spring flowering plants. Because they set their buds the season prior to the flower, fall-planted trees and shrubs will display their glory in the spring season in your garden. A few of our spring-flowering favorites are Crabapples, Redbuds, Serviceberry, Azalea and Viburnum. Or, add to your garden’s fall display by choosing Maples, Cherries, Burning Bush or Sweetspire.

Autumn is also a terrific time to install the new patio or walkway you’ve been thinking about. With the addition of a new patio or sitting area, you can expand your outdoor living space and enjoy the wonderful fall season the Midwest has to offer, as well as having the use of your new space when spring arrives.