Typically evergreen or deciduous perennials, with whorls of leaves, flowers with long tubes and 4-5 petals. Of the plants in cultivation they tend to be suitable for open sunny positions, in a rock garden setting, front of the border. Related to Galium, Phuopsis and Houstonia, all similar small perennials. In the Rubiaceae family, which has some very pretty genera, but also Coffea arabica, coffee, the worlds most important crop plant.
Although the flowers are very small they are produced in such abundance that they provide a valuable resource to visiting insects, especially small bees, flies and some butterflies e.g. small tortoiseshell.