As some leaves die, they produce chemicals called anthocyanins (also found in the skin of grapes and apples) from built up sugars. These chemicals produce a red pigment that can combine with green pigments left from chlorophyll and display different shades of red.

Why are the leaves on my plant turning red?

Vegetable plant leaves oftentimes turn red when there is a phosphorus deficiency in the soil. But it can also be caused by cold weather and too much rain. Too much rain can leach phosphorus out of the soil and cold weather spikes can sometimes stimulate red pigment in the plant.

What are three reasons why leaves turn red?

As some leaves die, they produce chemicals called anthocyanins (also found in the skin of grapes and apples) from built up sugars. These chemicals produce a red pigment that can combine with green pigments left from chlorophyll and display different shades of red.