Why do leaves turn red?

All gardeners in Washington State are aware of seasonal changes in leaf color. Many deciduous leaves turn some shade of red before they fall during the autumn months. The red coloration is due to the production of leaf pigments called anthocyanins, which are also found in red, blue, and purple flowers and fruits. But leaves can also turn red for reasons unrelated to autumn color development. This fact sheet will outline those reasons and explain when red leaves indicate the need for corrective action by gardener