Aloidendron barberae (Dyer) Klopper & Gideon F.Sm.
Common names: tree aloe (Eng.); boomaalwyn, mikaalwyn (Afr.); ikhala (Xhosa); umgxwala, indlabendlazi, impondonndo, inkalane-enkulu (Zulu)
SA Tree No: 28
Aloidendron barberae is a striking sculptural tree aloe bearing a rounded, neat crown. It was previously known as Aloe barberae. It forms an excellent focal point in the garden. It is easily distinguished by its grey, smooth bark, green recurved leaves and pink flowers during winter. It thrives in cultivation and is easily propagated. Due to its massive stem base, it should preferably not be planted close to any buildings.
Aloidendron barberae is Africa's largest aloe reaching up to 15 m in height and 0.9 m in stem diameter. The branching is forked or dichotomous and eventually forms a spreading, rounded crown. It leaves are arranged in a dense rosette, they are long, narrow, deeply channelled and curved. The leaf surface is dark green with a toothed margin. The inflorescence is simple or divided into three side branches. The racemes are cylindrical and its tubular flowers rose pink (green-tipped) and appear during June and July.
Distribution and habitat
Its habitat is subtropical coastal forests, kloofs and dry valleys in the summer rainfall eastern regions of southern Africa. Aloidendron barberae is widely distributed from near East London in Eastern Cape through the former Transkei area, KwaZulu-Natal, Swaziland and Mpumalanga and northwards to Mozambique and East Africa.
Derivation of name and historical aspects
This plant was first discovered by Mary Elizabeth Barber, who was a plant collector in the former Transkei. She sent specimens of the plant and its flowers to the Royal Botanic Gardens at Kew, where it was named by Dyer (1874) in her honour. Subsequently it was also found in the Tugela River Valley (KwaZulu-Natal) by the well known traveller, explorer and painter Mr. Thomas Baines in 1873. He sent a specimen to Joseph Hooker at Kew, where it was named in his honour. Although known for many years as Aloe bainesii, Aloe barberae was the name first given to this plant, and took precedence according to the International Code of Botanical Nomenclature. The genus name Aloe is derived from a Greek word and refers to the dried juice from the leaves. There were about 350 species of Aloe which are widespread in Africa and the surrounding islands, as well as the Arabian Peninsula. The genus has recently been reassessed and this plant has been renamed Aloidendron barberae.
This tree grows in warm, well-drained river valleys and coastal forest where the climate is mild and rainfall is at least 1 016-1 524 mm per annum and with little or no frost. The seeds often germinate in the shade of other plants and eventually outgrow their companion plants. The soil is usually a loam and humus rich. In habitat the plants are pollinated by sunbirds. The capsules ripen during late spring and release their seed which is wind dispersed.
Growing Aloidendron barberae
Aloidendron barberae is easily cultivated from truncheons as well as seed and smaller stem cuttings. It is fairly fast growing, but should be well watered and enough compost provided for optimal growth. It is sensitive to frost and in a frost-prone area should be protected in the first few years of its life. Always provide a well-drained site, on a slope is best. Enough space should be provided for its eventual size. The leaves may be attacked by aphids and scale insects, which are controlled with an oil-based spray
- Coates Palgrave, M. 2002. Trees of Southern Africa. Struik Publishers, Cape Town
- Leistner, O.A. 2000. Seed Plants of Southern Africa, Families And Genera, Strelitzia 10. NBI, Pretoria
- Smith,G.F. et al. 1994. Aloe barberae to replace A.bainesii. Bothalia 24(1)34-35.
- Nichols,G. 2001. A great sculptural species. Farmers Weekly 29June:p.87
- Ernst Van Jaarsveld, Personal communication
- Grace O.M., Klopper R.R., Smith G.F. et al. 2013. A revised classification for Aloe (Xanthorrhoeaceae subfam.Asphodeloideae). Phytotaxa 76(1)7-14.
Kirstenbosch National Botanical Garden
Plant Type: Succulent, Tree
SA Distribution: Eastern Cape, KwaZulu-Natal, Mpumalanga
Soil type: Sandy, Loam
Flowering season: Winter
PH: Acid, Neutral
Flower colour: Red, Pink
Aspect: Full Sun, Morning Sun (Semi Shade), Afternoon Sun (Semi Shade)
Gardening skill: Average