Why Leaves Change Color

Infographic: A few facts about why leaves change color with the seasons. Download a PDF to Share!

Chlorophyll Breakdown: The Key to Fall Colors

Why Leaves Lose Their Green

As daylight shortens and temperatures drop, chlorophyll production slows and eventually stops.
Chlorophyll, responsible for leaves’ green color, breaks down, causing the green to fade.

Revealing Hidden Colors

With chlorophyll gone, carotenoids (yellow, orange) and anthocyanins (red, purple) become visible.
These pigments, previously hidden, create the vibrant hues of autumn.

A Tree’s Winter Prep

The breakdown of chlorophyll is part of the tree’s preparation for winter, conserving energy as it enters dormancy.

Why Only Some Trees Lose Their Leaves

Deciduous Trees

Broad leaves are vulnerable to cold, so deciduous trees shed them in fall to conserve energy.
Chlorophyll breaks down, revealing the vibrant autumn colors.
This process helps them survive winter without the burden of maintaining large leaves.

Coniferous Trees

Needles or scales are built to withstand extreme weather.
A waxy coating and narrow shape help retain moisture and reduce water loss.
Evergreens keep their green foliage year-round, staying resilient even in winter.

How Temperature Influences Fall Colors

Wet Spring + Favorable Summer + Sunny, Cool Fall = Brilliant Colors

Warm, sunny days help leaves produce sugars.
Cool nights prevent sugars from leaving the leaves.
The trapped sugars create anthocyanin pigments, which produce reds, purples, and crimsons.
Carotenoids, responsible for yellow and gold, stay consistent year-round.

Soil Moisture & Weather Matter Too

Droughts or late springs can delay fall colors.
Warm autumns may also dull colors.