The family Rubiaceae, Madder or Bedstraw, consists of about 650 genera and 10,500 species worldwide. The majority grow in the tropical in subtropical regions and and have mostly woody stems. Those in temperate regions are herbaceous. All our Rubiaceae are of the "Bedstraw" type: sprawling, low growing annuals.
The flowers are usually small and inconspicuous, growing in clusters. They have a tubular 4-lobed corolla and 4 stamens.
The leaves are simple, entire (rarely lobed) and opposite or whorled. Stipules are often fused at the node and leaf-like, appearing like whorled leaves.The fruits are distinctly two-lobed, which dry and separate into 1-seeded nutlets with hooked bristles.
Economic uses include source of coffee, quinine and ipecac. They are also cultivated as ornamentals and for red dye.