🍁 Why Leaves Change Color in Autumn
The Hidden Chemistry Behind Fall Colors
The Big Idea
When autumn arrives, trees put on a spectacular light show—green leaves turn yellow, orange, red, and purple. But where do these colors come from? The truth is simple: the colors were always inside the leaves, just hidden by summer’s green. Autumn is when nature reveals its secret paintbox.
Science Spotlight 🔬 (Step by Step)
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Summer Green – Chlorophyll
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Leaves look green in spring and summer because they are full of chlorophyll, the pigment that captures sunlight to make food (photosynthesis).
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Chlorophyll is like the leaf’s solar panel.
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Autumn Arrives – Chlorophyll Breaks Down
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Shorter days and cooler nights tell the tree to prepare for winter.
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Trees stop making chlorophyll, and the green fades away.
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Hidden Pigments Shine
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Carotenoids (yellow & orange) are always present but masked by green.
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Anthocyanins (red & purple) are produced in autumn, helping protect leaves from sunlight and allowing trees to pull back nutrients before the leaves fall.
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The Result – Autumn Colors
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As green disappears, the yellows, oranges, and reds take center stage.
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Each tree species has its own “color fingerprint”—maples glow red, birches shine yellow, oaks turn brownish-gold.
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Why It Matters 🌱
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For the tree: changing colors = recycling nutrients and surviving winter.
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For us: it’s proof that nature’s beauty often hides beneath the surface, waiting for the right season to emerge.
Fun Fact 💡
The brightest reds happen when days are sunny but nights are cold—perfect conditions for anthocyanins to build up. That’s why some years look more colorful than others!
Mini DIY Demo – Leaf Pigment Detective
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Crush a green leaf in rubbing alcohol (adult help recommended).
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Place a drop of the liquid on filter paper (or coffee filter).
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As the liquid climbs, you’ll see different colored bands—green (chlorophyll), yellow/orange (carotenoids), maybe red (anthocyanins).
👉 This experiment shows the hidden pigments that appear naturally in autumn.
3-Line Summary
Leaves change color because chlorophyll fades in autumn.
Hidden pigments—carotenoids and anthocyanins—are revealed.
It’s a survival strategy for trees, wrapped in breathtaking beauty.