The pink sage is a fast growing many branched semi-deciduous shrub with aromatic heart shaped leaves which grows to a height and spread of 1.5m. It occurs on rocky hillsides with a scattered distribution through KwaZulu-Natal, Swaziland, into the Northern Provinces of South Africa and further into Zimbabwe.

The scientific name is derived from Ortho - erect & siphon - a flower tube, alluding to the erect flower tube and labiatus - meaning lipped, is also a reference to the flower.

Orthosiphon labiatus belongs to a very large internationally distributed family, which is widely cultivated for its herbal properties. This family includes many important herbs such as mint and rosemary and sage. The genus Orthosiphon is represented by nine South African species, all distributed in the eastern and northern parts of the summer rainfall regions.

Growing Orthosiphon labiatus

Orthosiphon labiatus is a very popular garden plant as it is hardy to a moderate degree of frost and extreme drought once established. It is prized for its showy display of pink - mauve sage like flowers which are carried on the shrub for a large part of the year, mainly through the summer months. It should be planted in full sun for best flowering, but will grow equally well in semi-shade. Although it is drought hardy and will grow under extreme conditions, it thrives when planted in rich, deep, composted garden soil and kept well watered.

It is useful for mass planting in large areas such as parks or large flower beds as it makes a wonderful display when used in this manner. For the smaller garden it can be planted in small groups or individually as part of a mixed backdrop or as a shrubby border under trees. The pink sage is also useful for attracting butterflies to the garden.

The plant may be cut back to one third of its height every couple of years to rejuvenate the woody growth. This should be done before the onset of its summer growing season and followed by a thick dressing of compost which can either be worked into the soil around the bush or left as a thick organic mulch. This is also a good time to apply a balanced fertilizer followed by a good deep soaking of water.

The plant can easily be propagated from seed or cuttings however the seedlings are so fast growing that propagation from cuttings is rarely necessary. Sow seed in spring in fine potting mix and cover very lightly. Keep the trays in a semi-shaded position until they have germinated which may take from two to four weeks. Transplant the seedlings into individual containers when they are large enough to handle.

References

• Arnold, T.H. & De Wet, B.C. (Eds) 1993. Plants of southern Africa: names and
  distribution. Memoirs of the botanical Survey of South Africa No 62.
• Joffe, P. 1993 The Gardeners Guide to South African Plants. Tafelberg Publishers
  Limited: Capetown.
• Joffe. P. 2001.Creative Gardening with Indigenous Plants, a South African guide.
  Briza Publications: Pretoria.
• Pooley. E 1993. The complete field guide to Trees of Natal, Zululand & Transkei.
  Natal FloraPublications Trust: Durban.

Andrew Hankey
Witwatersrand National Botanical Garden
December 2001.