For the identification of insects and other fauna and flora of South Africa.

Saturday, March 16, 2013

Summer-flowering Impala Lily (Adenium swazicum)

Family Apocynaceae
Found in open woodland, usually on sandy brackish flats in South Africa ( Mpumalanga and northern parts of KwaZulu-Natal ), Swaziland and Mozambique at altitudes of 300-400 m. It is a small shrub, up to 650 mm tall, with a large, buried, succulent stem. The stem produces several greenish white or dirty-grey branches. The simple leaves are long, tapering and smooth, 40-130 Í 7-30 mm, and borne in terminal clusters. They are often folded, broader at the apex than at the base and the midrib is prominent beneath. The flowers are pink to deep purple, darker in the throat and appear together with the leaves.
 Flowering occurs from January to April. A few specimens have been grown in the rockery at the Durban Botanical Garden for many years but have never been seen to set seed. Adenium multiflorum is distinguished from A. swazicum by the upper portion on the inside of the corolla that is hairy and not smooth, by the dark border on the petals and by the flowers that usually appear before the leaves (in A. swazicum the leaves and flowers appear simultaneously).
 In the garden
The attractive flowers of adeniums and their interesting stems make them desirable for the garden. Generally most adeniums are cultivated from seed. Adenium multiflorum and A. obesum are the most well-known and widely cultivated members of the genus. They are slow-growing but long-lived plants and thrive in sandy soils in hot areas. These extremely drought-resistant plants should be planted in well-drained soil and in full sun. They are definitely not suitable for cold, damp gardens as they are very sensitive to frost. In warm gardens that experience occasional frost they should be given a very warm, sheltered position.
 Adenium boehmianum, A. multiflorum, A. obesum and A. swazicum make good accent plants in a rock garden, especially when grouped together with other caudiciform succulent plants such as species of Pelargonium, Cissus and Cotyledon ; A. boehmianum is rarely cultivated. All species need full sun, lots of water (except during the dormant phase) and must have good drainage. Plants are leafless for most of the year. It is said to be difficult to transplant mature plants owing to the large tuberous rootstocks. Adenium swazicum is an ideal subject for container cultivation.