Krans aloe  (Aloe arborescens)

Classified as Vulnerable (VU) in Malawi on the Southern African Plant Red Data List (3), and listed on Appendix II of CITES (1).

The krans aloe is a dense, many-branched, succulent shrub (2) (4), with heads of green leaves arranged in attractive rosettes (5). These leaves are sickle-shaped and have margins armed with sharp, pale green teeth (6). The flowers of the krans aloe are borne on elongated, conical stems (2), forming striking spikes of colour, most commonly scarlet or deep orange, but occasionally yellow (4). Two or more of these distinctive flower stalks, measuring up to 30 millimetres long (6), arise from each rosette of leaves (5). The species name, Arborescens, means tree-like in Latin and refers to the tall stems that the krans aloe forms, while the common name refers to its habitat; a krantz being a rocky ridge or cliff (5).

This widely distributed aloe occurs in South Africa, through Swaziland, eastern Zimbabwe and Mozambique, to Malawi (1) (2).

The krans aloe is one of the few aloes that can be found growing from sea level right up to the tops of mountains (5). It is usually found on rocky slopes and exposed ridges (5) (6), but can also be found in dense bush and forest (4).

The large, colourful flower spikes of the krans aloe appear in the cool winter months of May and June (2) (5). Like other species of aloe, the flowers of the krans aloe produce nectar, attracting sunbirds and bees, which pollinate the plant as they feed (5). While each flower of an Aloe species contains both male and female organs, (the stamens and pistil), it cleverly avoids the possibility of self-fertilisation as the stigma is able to recognise its own pollen, and only accept pollen from other plants (7). The sap-rich leaves of the krans aloe are used as a first aid treatment for burns (6)

While in most of its range the krans aloe is a common and widespread species (3) (6), in Malawi, agriculture is encroaching on the krans aloe’s habitat, and the species is now classified as threatened in that region (3).

The remaining populations of kranz aloe in Malawi are well protected (3), and it also occurs within the Cape Floral Kingdom, a ‘hot-spot’ of plant diversity in which there are a number of protected areas (8). While Malawi populations are threatened, overall this species future is probably secure, due not only to its wide natural distribution and abundance, but also as it is one of the most widely cultivated aloes in the world (5).