The majority of Old World succulent monocotyledons are grouped into the Aloaceae, a medium sized family of rosulate leaf succulents including Aloe, Astroloba, Bulbine, Chortolirion, Gasteria, Haworthia and Poellnitzia. The Aloaceae are distributed across southern Africa, Arabia, Madagascar and the Mascarene Islands. A few Bulbines are found in Australia. The largest genus is Aloe with more than 400 species.
You can download higher quality images by clicking on the pictures below.
|
Aloe Linnaeus (1753)
Greek: alsos, Arabic: alloeh =bitter
Over 450 species of Aloe have been described with diverse forms and sizes. The genus includes small grass-like herbs and stemless succulent rosettes a few inches tall to larger species with stout 60ft trunks, occupying the ecological niche of trees. Aloes, with their waxy leaves, are well-adapted to harsh climates with infrequent precipitation. They can flower many times with clusters of yellow, orange or red tubular flowers, angled downwards on a simple or branched inflorescence.
Aloes are distributed across sub-Saharan Africa, Madagascar, and Arabia. Aloes feature in prehistoric rock art by bushmen, and have been cultivated for thousands of years. Although Aloes are mentioned in the Bible, this probably refers to another resinous plant. However, the Egyptian Ebers Papyrus (ca. 1552 BC) refers to the medicinal value of Aloes,
which were also used in embalming. Aloes were known to the Greeks by 400 BC. The Greek herbal of Dioscorides (41-68 AD) recommends Aloe applied externally for wounds, hemorrhoids, ulcers and hair loss, and internally as a laxative.
Aloe vera became so widely grown as a medicinal plant in ancient times that its exact region of origin is a mystery. This species is of considerable economic importance and extracts are included in all manner of pharmaceutical preparations for the skin, treatment of burns and for ingestion.
Aloe ferox and other species are cultivated for the bitter properties of the sap (bitter Aloes) which discourages predators. These two species are the basis of a £multi-million industry in South Africa.
It is important to use the correct species of Aloe for medicinal preparations, as some species e.g. Aloe venenosa are poisonous. Toxic reactions by sensitive individuals to Aloe barbadensis (Aloe vera) have been reported, despite its widespread use.
Cultivation: Partial to full sun suits most species of Aloe. The larger Aloes enjoy more direct sunlight than the smaller species as they would normally grow through and above protective vegetation. However, strong sunlight may be needed to develop the attractively bronzed foliage that some species develop in their habitat. Many Aloes produce spectacular racemes of packed tubular yellow, orange or red flowers and are of considerable horticultural merit for the tropical garden or larger glasshouse. Numerous small species can be grown and will produce their showy flowers on a sunny window ledge. Aloes may be grown from seed but hybridise freely between species in flower at the same time. Some inter-specific Aloe hybrids are available as well as Aloe x Gasteria hybrids.
Watering regimes should reflect whether the plant is from a summer or winter rainfall area. Some species can be remarkably sensitive to water at the wrong time of year while they are resting. Although most species tolerate cool dry winter conditions, few species are sufficiently hardy to withstand cold wet winter weather in the UK and similar climates. Notable exceptions include Aloe aristata and Aloe polyphylla.
|
Aloe somaliensis
Bookstore
Aloes
Monocotyledons
Cacti
Succulent Plants
Arid Gardening
Webmaster's Choice
|