Salvia schlechteri Briq.
Common names: Xobo Valley sage
Little is known about Salvia schlechteri, but with its unusual foliage and pale blue flowers, it deserves a place amid a herbaceous border or summer display planting.
Salvia schlechteri is a perennial shrub which can become woody at the base. The erect stems, up to 300 mm, are square as is typical of Lamiaceae, and may be branched. Leaves are a vibrant light green and deeply divided giving them a feathery appearance. Both stems and leaves are scattered with glandless hairs and oil globules although the plant is not particularly aromatic.
Pale mauve and white flowers appear during summer. Black or dark brown nutlets are visible at the base of the calyx and fall out when ripe. The Xobo Valley sage is a quick growing perennial, but has a semi-dormant period over winter.
Salvia schlechteri requires further study to determine its conservation status and is currently Red Listed as data deficient (DDD). According to the SANBI Threatened Species Programme, it is likely to be threatened by overgrazing and expanding rural settlement. Too little is known about this species to determine its threat status accurately.
Distribution and habitat
This species is only known from the Eastern Cape Province of South Africa. Minimal details are available about its locality and it is noted as occurring in the Xobo Valley of the former Transkei, growing in full sun in rich loamy soil of the grasslands.
Derivation of name and historical aspects
Salvia schlechteri was first described in 1903 by a Swiss botanist, John Isaac Briquet (1870-1931). Briquet was the curator of the Conservatoire Botanique in Geneva.
Salvia is derived from the Latin salvus, meaning uninjured, whole, safe, well or sound, and salvere, to be in good health, referring to the medicinal value of the plants.
The appellation schlechteri honours its first collector, Friedrich Richard Rudolf Schlechter (1872-1925), who was a German botanist and taxonomist that travelled to Africa to do botanical explorations from 1892-1895. He collected the first herbarium specimen of Salvia schlechteri on 18 January 1895 in the Transkei. He collected widely and his collections are too numerous to list. His extensive herbarium in Berlin was destroyed in the 1945 bombing during the Second World War.
Salvia is the largest genus in the Lamiaceae family and consists of approximately 900 species made up of annuals, perennials and shrubs. They are widely distributed around the world in warm temperate and tropical regions. Twenty-seven species are found naturally in South Africa. Noteworthy South African sages are S. africana-lutea, S. africana-caerulea, S. chamelaeagnea, S. muirii and S. dolomitica. Sages are commonly grown as ornamentals.
Bees and insects are attracted to salvia flowers. The filaments of the stamens are hinged, which gives them mobility, allowing them to attach pollen to visiting pollinators.
The flowers of Salvia schlechteri are adapted for bee pollination. The lower lip of the flower is a platform on which the bee lands. As the bee probes for nectar, it presses against the hinged filament of the stamen, which causes the stamen to move down and the anther to touch the bee, rubbing pollen onto the bee's back. When the bee enters another flower of the same species, the pollen will rub against the stigma of the other flower and, if receptive, cross-pollination will be successful.
Salvia schlechteri can be used as an attractive, summer-flowering shrub in any herbaceous border and is suitable for large or small gardens. This sage is a wonderful addition to any garden planting with its vibrant green foliage and pale blue flowers. As it occurs naturally in grasslands, it is best suited to dense plantings with other herbaceous perennials and grasses. It is suitable as a foreground or midway planting. When it goes dormant in winter, annuals or other seasonal herbaceous perennials can be grown in the same area reducing the open space left by its vacancy in the border planting. Salvia schlechteri is a wonderful garden specimen and water wise.
A hybrid between Salvia schlechteri and S. muirii is also in cultivation and it makes a wonderful display perennial which does not go fully dormant as does the pure species.
Growing Salvia schlechteri
Salvia schlechteri is best grown in open ground in full sun. It requires well-drained, composted soils. This sage will survive with regular watering in summer. No extra feeding is necessary for strong, healthy growth in good soils, although an occasional foliar feed would do no harm and the plants will tolerate and respond well to general fertilizing. The plants can be pruned back, almost to the ground, every year when they go dormant.
Young plants can be planted out at the end of spring. Salvia schlechteri is easily combined with most flowering perennials or shrubs that contrast with its foliage, such as Diascia integerrima, Silene bellidioides and Lasiospermum bipinnatum.
New plants are easy to propagate from seed and cuttings. Sow seeds from late spring to early summer into a general potting soil mix. Seeds germinate quickly and seedlings can be transplanted into well-drained potting soil once the first pair of true leaves appears.
Take semi-hardwood tip cuttings in spring and summer. Cuttings must be without terminal flowering buds. Using a rooting hormone will improve the chance of root development. Place in a rooting medium consisting of 50% fine-milled bark or peat and 50% perlite. Keep cuttings under mist or enclose in plastic bags to retain humidity. Keep warm but out of direct sunlight. Cuttings should root in 3-6 weeks.
The plants do not have any major pests. Mealy bug and aphids do appear from time to time, but are easily managed with suitable control methods.
- Hedge, I.C. 1974. Revision of Salvia in Africa including Madagascar and Canary Islands. Notes from the Royal Botanic Garden Edinburgh 33(1).
- Smith, C.A. 1966. Common names of South African plants. Memoirs of the Botanical Survey of South Africa No. 35.
Kirstenbosch National Botanical Garden
Plant Type: Perennial
SA Distribution: Eastern Cape
Soil type: Sandy, Loam
Flowering season: Early Summer, Late Summer
PH: Acid, Neutral
Flower colour: White, Mauve/Lilac
Aspect: Full Sun
Gardening skill: Average