Desert rose - Adenium obesum

The desert rose is usually simply referred to as Adenium obesum, however, the fuller name is A. obesum var obesum. In older literature desert rose may be referred to as A. arabicum. 

The genus Adenium ιs a genus of spectacular succulents. The genus Adenium contains only one species, which is divided into several sub- species or botanical varieties. Some authors, however, recognize separate species. All are native to semi-arid climates. The name Adenium is derived from the Arabic name for the plant, Oddaejn, which means Aden, the former name for Yemen. 

A. obesum is found in sub-Saharan Africa from The Sudan into Kenya and westward to Senegal, and south to Natal and Swaziland. A few occur in the SW corner of the Arabian peninsular (Yemen). 

Adeniums are in the Apocynaceae (dogbane family), which includes mostly tropical species, such as Beaumontia, Carissa, Allamanda, Mandevillea, Nerium, Plumeria, and Tabernaemontana, which are widely used in warm climates. Most of these plants produce varying amounts of milky sap, which can cause skin irritation or, as with desert rose, more severe internal poisoning. 

Tribes in various parts of Africa have used adenium sap in a mixing to tip weapons and arrowheads for hunting game. Today, poison preps are used more for homicidal purposes, although most hosts will eat or drink a small portion of the offered fare in front of guests to establish good faith.

Adenium obesum contains active cardiac glycosides that have been tested as cardiac drugs but are not in use because of the severe side effects.

In nature, the adenium is quite variable but can form a small, thick-trunked tree or large shrub. However, with its unusual branch shapes and controllable size, the adenium is becoming popular in bonsai gardens. Their striking forms are further enhanced by some of the showiest flowers of all succulents, often borne in masses over a long season.

Adenium can be propagated by cuttings or by seeds. It takes about 6 months or longer from seed to flowering. You can make a new hybrid by artificially crossing between 2 different cultivars or different species. Some adenium hybrids can have many branches, some very few. However, branching can be induced by pinching the top. 

Desert roses are not finicky plants, although they have received that reputation. The plants normally grow in climates with summer rains and dry winters. They prefer frequent fertilization and should never be allowed to freeze.