Why are newly grown leaves red?

Question

After a period of heavy rain, several trees in my garden will put out an impressive burst of new leaves, with an incredible vibrant red colour, almost the colour of port wine. The new leaves will then slowly turn green. I understand that the leaves turn green once they start producing chloroplasts and chlorophyll, but what is responsible for this initial red colour that is so very vibrant? And what biological role does it play?

Answer 1

Hello!

Some studies have stated that the beginning red color is due to anthocyanins! These chemicals may protect the plant from the cold, ultraviolet rays, pollution, and other types of damage.

It is also thought that the red color is from not having sufficient chlorophyll.

Hope this helps!!

Answer 2

There are a number of different theories as to why young plant leaves are red. The red appearance is caused by anthocyanins, the same molecule in blueberries that makes them dark in high concentrations and are what people refer to when talking about their antioxidants. One theory suggests that the red or dark color produced by anthocyanins helps protect young leaves against herbaceous insects, as insect eyes do not pick up on reds as well as greens and yellows. Another thought is that it is because anthocyanins are such good antioxidants. The sun's energy is able to produce oxygen free radicals, which damage cells. So, if these leaves do not yet have enough chlorophyll to absorb the energy, anthocyanins are able to stop the damage of the oxygen free radicals and allow the leaf to keep growing without any damage to its organelles or DNA.