Ocimum labiatum, the Pink Sage, is an attractive plant that produces masses of pink or mauve flowers from early summer till autumn.
Ocimum labiatum (=Orthosiphon labiatus), Pink Sage or Shell Bush, is a very ornamental garden shrub. It bears a profusion of pink to mauve flowers from early summer to late autumn. It has an added advantage that it is happy to grow in full sun or partial shade.
Family: LAMIACEAE (Mint family)
- Ocimum is the ancient Greek name for Basil, which is a member of this genus.
- labiatum is Latin and means lipped, referring to the two prominent lips on the flowers.
Common Names: Pink sage, shell bush (Eng) and pienksalie (Afr).
Size: 1 – 1.8 m by 1 – 1.5 m.
- Sprays of fine pink to mauve flowers.
Colour: Pink to mauve.
Flowering Months: Nov to Apr.
Fragrance: Crushed leaves are aromatic.
- Evergreen to partly deciduous.
- Light green, heart-shaped leaves.
- Leaf margins are softly serrated, making the leaves look like small mulberry tree leaves.
- The leaves and stems are sparsely hairy.
The pink to mauve flowers of Ocimum labiatum, the Pink Sage, are borne on slender spikes that are up to 18 cm long, with clusters of 6 to 8 flowers that are between 10 and 20 cm apart.
The individual flowers of Orthosiphon labiatum is up to 2 cm long with extended stamens and style, the stamens tend to curve downwards and the style upwards.
- Seeds are contained within a capsule within the calyx.
- Stems are sparsely hairy.
In the Garden:
- Ocimum labiatum is a wonderful garden plant because it flowers profusely for long periods each summer.
- It may be planted individually but looks best when planted in groups of three or more plants.
- A good choice for an informal border or mass planted as a ‘taller’ groundcover.
- It is equally at home in full sun or semi-shade.
- Once established it is surprisingly frost and drought hardy.
- Plant in well composted soil.
- A wildlife friendly shrub, attracting insects and birds.
- A quick growing shrub, flowering within the first year of been planted out.
Soil Needs: Will grow in most soil types.
An Ocimum labiatum, Pink Sage, grown on a terrace next to a retaining wall, hanging over the wall and so softening the wall.
- A low maintenance plant.
- Feed regularly with compost mulches, organic 3:2:3 and bonemeal.
- Protect young plants against the cold in winter.
- Cut back to knee height in spring after the threat of frost is past.
Cold Hardiness: Cold hardy, but protect young plants.
Water Requirements: Drought hardy, but thrives on regular summer water.
Light Requirements: Full sun and partial shade.
- Insect-eating birds are attracted to the insects that visit the flowers.
Insects and Butterflies:
- Flowers are visited by bees, carpenter bees and adult butterflies.
- Two labdane diterpenoids compounds isolated from this plant in 2007 show promise in combating tuberculosis and breast cancer in humans.
Notes of interest:
- This plant was being researched at the Tshwane University of Technology as a potential commercial source of essential oils.
- It also has potential to be used to absorb heavy metals from old goldmine dumps, and so rehabilitate them.
- Occurs naturally from southern KZN, Swa, M, L, NWP northern G and also in Zim.
- Endemic to southern Africa.
- It may be found on rocky outcrops in dry, wooded hillsides.
Besides being an attractive garden plant, Ocimum labiatum, may be used to extract heavy metals from old mine dumps, and so help clean our environment.
© Malcolm Dee Hepplewhite & Witkoppen Wildflower Nursery, (Text and Photographs) 2012 & 2018.