Rubiaceae: Coffee Family

While this familly recently only included 6,500 species in 450 genera, it has recently been expanded to about 600 genera and 10,000 species. Not only is this family large, but it contains some very important plants. Coffee is in the family. Noni, Morinda citrifolia, a pacific cure-all plant has been widely used for treating cancer. Gardenias, Gardenia spp, who have sweet smelling flowers, are very popular ornamentals. Ixora spp is a popular ornamental plant as well with its bright red, white and blue flower clusters.

Systematics: A big key to identifying this family is to look for the simple opposite leaves and interpetiolar stipules. The ovaries are also inferior. There are usually 2 carpels for each of the many locules. The stamen alternate with the lobes and are equal in number to the petals. There are usually 4-5 petals (3-10 possible). The calyx lobes are often very reduced and sometimes lacking!

Specimens List

Noni (Morinda citrifolia)

Foul tasting fruit that has been used as a cure-all plant in Pacific medicines.

Gardenias (Gardenia spp)

There are around 250 species of Gardenias. Most have very sweet scented flowers.

Ixora spp

This is a common ornamental plant.

Bedstraws (Galium spp)

There are almost 400 species of bedstraws in this genus. Baby's Breath is one type of bedstraw.

Coffee (Coffea spp)

There are several Coffea species that are grown for their beans but Coffea arabica is said to taste the best.

Links to more information

Dr Carr's UH Botany Website