Variegation is the appearance of differently coloured zones in the leaves and sometimes the stems and fruit of plants. Species with variegated individuals are sometimes found in the understory of tropical rainforests, and this habitat is the source of a number of variegated houseplants. Variegation is caused by mutations that affect chlorophyll production or by viruses, such as mosaic viruses, which have been studied by scientists. The striking look of variegated plants is desired by many gardeners, and some have deliberately tried to induce it for aesthetic purposes. There are a number of gardening books about variegated plants, and some gardening societies specialize in them.

The term is also sometimes used to refer to colour zonation in flowers, minerals, and the skin, fur, feathers or scales of animals.

Chimeral variegation occurs when a plant contains tissues with more than one genotype, some producing chlorophyll and others not. To preserve variegation, plants must be propagated using methods like stem cuttings or bud grafting. Other types of variegation include reflective variegation, which results from light reflection off the leaf surface, and venal variegation, where leaf veins are highlighted in white or yellow.

Pigmentary variegation is caused by the masking of green pigment by other pigments, such as anthocyanins. Pathological variegation can occur due to virus infections, leading to characteristic patterning on the leaf surface. Some variegation patterns might serve as a defensive masquerade strategy against leaf-mining insects.

Variegated plants have been valued by gardeners for their ability to add visual interest to gardens. They are often featured in gardening books and societies dedicated to variegated plants. In recent years, variegated plants have even sold for thousands of dollars at auctions.