Indigo is a deep color close to the color wheel blue, as well as to some variants of ultramarine, based on the ancient dye of the same name. The word "indigo" comes from the Latin word indicum, meaning "Indian", as the dye was originally exported to Europe from India.
Indigo dye is an organic compound with a distinctive blue color. Indigo is a natural dye extracted from the leaves of some plants of the Indigofera genus, in particular Indigofera tinctoria; dye-bearing Indigofera plants were commonly grown and used throughout the world, in Asia in particular, as an important crop, with the production of indigo dyestuff economically important due to the historical rarity of other blue dyestuffs
Indigofera is a large genus of over 750 species of flowering plants belonging to the pea family Fabaceae. They are widely distributed throughout the tropical and subtropical regions of the world.
Indigofera tinctoria, also called true indigo, is a species of plant from the bean family that was one of the original sources of indigo dye.
Indigofera suffruticosa, commonly known as Guatemalan indigo, small-leaved indigo, West Indian indigo, wild indigo, and anil, is a flowering plant in the pea family, Fabaceae.
Baptisia is a genus in the legume family, Fabaceae. They are flowering herbaceous perennial plants with pea-like flowers, followed by pods, which are sometimes inflated. They are native to woodland and grassland in eastern and southern North America. The species most commonly found in cultivation is B. australis.
Arabis hirsuta, known as hairy rock-cress, is a flowering plant of the genus Arabis in the family Brassicaceae. In previous North American works, this species has been broadly defined to include plants native to Europe, Asia, and the northern half of North America, but is now more often restricted to a narrower subgroup restricted to Europe.
Indigofera australis, the Australian indigo or Austral indigo, is an attractive species of leguminous shrub in the genus Indigofera. The genus name Indigofera is Neo-Latin for "bearing Indigo". Australis, from the Latin, means not “Australian” but "southern", referring to the geographical distribution of the species.
Blephilia hirsuta is an herbaceous perennial of the mint family Lamiaceae native to eastern North America. It is commonly called hairy wood-mint or hairy pagoda plant.
Indigofera decora, commonly known as summer wisteria, is a species of shrub native to China and Japan that has since been introduced to Australia and Sri Lanka. A member of the genus Indigofera, its family is Fabaceae and is used primarily for decorative purposes, though it has also been used to make indigo-colored dye.
Indigofera pendula, the weeping indigo, is a species of flowering plant in the family Fabaceae, native to south-central China. Its cultivar 'Shangri-la' has gained the Royal Horticultural Society's Award of Garden Merit.
Indigofera cordifolia, the heart-leaf indigo, is a species of flowering plant in the family Fabaceae. It is found from the Cape Verde Islands, across the Sahel to Oman, the Indian Subcontinent, Guangdong in China, and some of the islands of Indonesia, and it has been introduced to the Northern Territory of Australia. A glycophyte adapted to sandy soils, it is considered a weed in some situations, but can also improve crop yields due to its nitrogen-fixing ability.
Indigofera spicata, the creeping indigo or trailing indigo, is a species of flowering plant in the family Fabaceae. It is native to Sub‑Saharan Africa, Madagascar, Mauritius, Réunion, and Yemen, and has been introduced to the southeastern United States, various Caribbean islands, Brazil and other locations in Latin America, various Pacific islands, and New South Wales and Queensland in Australia. It was considered to be a promising forage plant, and then shown to be toxic to nearly all livestock, but it is possible that the experiments were conducted on the similar Indigofera hendecaphylla, leading to some confusion.
Indigofera hendecaphylla, the creeping indigo or trailing indigo, is a species of flowering plant in the family Fabaceae. It is native to the Old World Tropics and Subtropics, and has been introduced to various locales, including Japan and Australia. It was widely introduced as a forage plant when it was thought to be conspecific with Indigofera spicata, and then shown to be toxic to nearly all livestock, with some uncertainty as to which species was tested.
Indigofera linifolia, the narrowleaf indigo, is a species of flowering plant in the family Fabaceae. It is very widely distributed from Sudan eastwards to the Indian Subcontinent, Southeast Asia, Malesia, New Guinea and Australia, and it has been introduced to Réunion and New Caledonia. Livestock can consume it as fodder, and in times of famine humans can grind and bake the seeds into a bread. It grows on dry slopes, grasslands, and riversides.
Indigofera cassioides, the cassia indigo, is a species of flowering plant in the family Fabaceae. It is native to the Indian Subcontinent, Southeast Asia, southeast and south-central China, and Taiwan, and has been introduced to Sri Lanka and Kenya. Local artisans use its leaves to produce a blue dye.
Indigofera arrecta, variously called the Bengal, Java, or Natal indigo, is a species of flowering plant in the family Fabaceae. It is native to Sub‑Saharan Africa, the Arabian Peninsula, and Madagascar, and has been introduced to the Indian Subcontinent, Southeast Asia, some of the islands of Indonesia, the Philippines, and Queensland in Australia. Today it is occasionally used as a green manure, but historically was a major source of Indigo dye, with 600,000 hectares under cultivation in India in 1896, declining to a few thousand hectares 60 years later.
Indigofera amblyantha, the Chinese indigo or pink-flowered indigo, is a species of flowering plant in the family Fabaceae, native to central and southern China. A non‑climbing shrub reaching 6 ft (2 m), it blooms from May to September, and is recommended for hedges, borders, massing, and containers.
Indigofera candicans, the white-leaved indigo, is a species of flowering plant in the family Fabaceae, native to the Cape Provinces of South Africa. The stems and the undersides of the leaves are white.
Indigofera miniata, the scarlet pea or coastal indigo, is a species of flowering plant in the family Fabaceae, native to the US states of Kansas, Oklahoma, Texas, Alabama, and Florida, and to Mexico, Guatemala, and Cuba. It is a prostrate perennial with stems that are about 60 cm (2 ft) long, and salmon pink flowers.
