10/16/2026
Why Do Leaves Change Colour in the Fall? 🍁
Deciduous trees are the ones whose leaves change colour in autumn. For most of the year, their leaves stay green because chlorophyll helps them absorb sunlight during photosynthesis. The leaves then turn that energy into sugars that nourish the tree.
As fall arrives, temperatures cool and there are less daylight hours. This is when chlorophyll in the leaves begins to break down.
As the green fades, yellow and orange pigments that were already present, become visible. The colour of the leaves looks different every year. The temperature, the amount of light, and the water supply all determine the intensity of the leaves' hues and how quickly they change colours.
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