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Is Leaves Changing Color A Chemical Change? Real Reason Will Shock You!

Isn’t it strange that your favorite plant or tree suddenly changes the color of its leaves to yellow, brown, orange, or red from green?

The leaves changing their color indicates a chemical change occurring annually during fall (September to November) in deciduous trees right before shedding their entire foliage.  

People believe that the leaves changing colors is due to physical or environmental change or injury.

Although the environment has much to add to this phenomenon, a deeper understanding will surprise you!

The Color Change In Plants [Explained]

The leaves of all plants are green, except in some parasitic species or in variegated varieties or cultivars.

The green color in plant leaves is actually due to the presence of a pigment, chlorophyll, in all the green plant parts.

Additionally, chlorophyll remains in the chloroplast (an organelle inside the plant cells) of each and every cell in the green areas of the plants.

Do You Know?

The green parts of the plant, leaves, petioles, stems, peduncles, branches, sepals, etc., all have chlorophyll as they are exposed to light.

However, roots don’t have any chloroplast in them, so they have a pale-brown look.

Chlorophyll allows the plant to capture sunlight energy and prepare food (glucose) in these green regions of the plant.

Image illustrates leaf color change according to seasons
Deciduous trees have the ability to shed their leaves and regain new green leaves in spring.

Annually broadleaved deciduous plants end their phenological cycle for the year. So, the chlorophyll present in these green parts slowly deteriorates due to chemical changes.

The leaves changing their colors from green to red, yellow, brown, or orange usually happens during fall (November to October) in such plants.

After the leaves turn their color, they drop, but the plant grows new leaves again in spring after escaping the dangers of winter frost.

Is Leaves Changing Color A Chemical Change?

The leaves change their colors due to deterioration of chlorophyll pigment. Hence, it is a chemical change.

Chlorophyll pigment is present in the leaves throughout spring and summer (warmer months), letting the plant photosynthesize profusely and store food products to equip it for the harsher fall and winter. 

However, in fall (or autumn), leaves slowly lose their green color, turning red, yellow, orange, or brown, resulting from decreasing chlorophyll and increasing anthocyanins.

Image illustrates color change in leaves due to plant pigments
The green color in the fresh leaves is replaced by yellow, orange, or red due to the natural aging process.

As the fall approaches, sunlight gets less intense, and days get shorter and cooler, prioritizing plants to prepare and store their food for the winter.

Fun Fact!

Chlorophyll helps to prepare food for plants but takes a lot of cellular energy during light absorption.

However, anthocyanins protect the leaves from direct sunlight damage and prevent chlorophyll from absorbing the light energy.

Hence, anthocyanins protect the plant from getting a lot of sunlight, discouraging sunburns, and preventing undesirable cellular energy expenditure. 

The climatic shifts and clocked circadian rhythms influence a chemical change in plants signaling them to shut down chlorophyll production, changing the color of the leaves.

Likewise, anthocyanin makes the leaf red, but other pigments also influence the leaf shade.

Some pigments include carotenoids and flavonoids that impart yellow color and carotenoids that turn the leaves orange.

From Editorial Team


Prepare biodegradable confetti to use the colorful leaves during fall festivals.

Collect the leaves, pile them up, punch holes using a paper hole puncher, and use!