The leaves of some plants are red, why can photosynthesis take place?

Plant leaves, which are often referred to as “green factories” by people, are known to require chlorophyll for manufacturing organic substances through photosynthesis.

However, some plants, such as rice, sugar beet, red amaranth, and autumn begonia, have leaves that are commonly red or purple. Can these leaves still perform photosynthesis?

Yes! These red-colored leaves also contain chlorophyll. The reason these leaves appear red is mainly due to the presence of anthocyanins, which are red pigments that overshadow the green color of chlorophyll.

To prove this, it’s not difficult at all. Just briefly dip the red leaves in hot water, and the truth becomes clear. Anthocyanins are highly soluble in water, while chlorophyll is not. In hot water, anthocyanins dissolve away, leaving the chlorophyll intact in the leaves. After boiling, the leaves change from red back to green, demonstrating the presence of chlorophyll in red leaves.

Additionally, many underwater plants like seaweed and kelp are often red or brown. Despite their color, they also contain chlorophyll, which is simply masked by another pigment—brown algae pigments.

Furthermore, certain plants like maple and oak have leaves that are initially green but turn red in autumn. This change occurs because chlorophyll is broken down, allowing the red pigment anthocyanin to become visible.