The Rubiaceaeare annual orperennial herbaceous plants, shrubs ortrees. The familyconsists of 611 genera andof approximately 13,000 species spread in the greatest variety in the tropical climatic zones of the world. Characteristic of the speciesof the familyis that their leaves are arranged oppositely and quite often several of them in nodes. Their flowershave a four-lobed corolla accreted at the bottom to form a tube.
The familyalso includes the coffee tree (Coffea arabica L.). In Bulgaria there are naturally spread 6 genera withapproximately 60 species of herbaceous plants orsemi-shrubs.