university of kwazulu-natal faculty of science and agriculture school ...

The flower colour varies among the species in Plectranthus, either being white, blue or
mauve to pink. At the end of February, the plants begin to develop flowerbuds and reach
full bloom between March and April. While some species of Plectranthus grow as
upright shrubs to a height of approximately 1.5 meters, for example, ecklonii, fruticosus
and hadiensis, others occur as groundcover plants, varying between 10 to 30 centimetres
in height, for example madagascariensis and saccatus. Plectranthus hadiensis can be
easily identified because of its large, hairy leaves.
Figure 13: Plectranthus hadiensis (picture courtesy of Prof. N. Crouch)
Species of Plectranthus are used as ornamental, economic and medicinal plants.
The phylogeny of Plectranthus was well documented by Paton et al. (2004) and Lukhoba
et al. (2006) based on its DNA sequence and augmented morphological data of the genus.
This information was presented in the form of a cladogram (figure 14) which divided the
Plectranthus genus into two clades or groups. Clade 1 contains Plectranthus species
formally known as Coleus and are grouped together based on their
ethnobotanical/medicinal uses with Clade 1b containing a greater number of medicinally
active species than Clade 1a. The groups in bold in figure 14 all have reported medicinal
uses. Of the three subclades, subclade 1b seems to be the most widely used medicinally,
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