It is an evergreen or drought-deciduous succulentshrub (which can also lose its leaves during cold spells, or according to the subspecies or cultivar). It can grow to 0.12–5 m (0.39–16.40 ft) in height, with pachycaul (disproportionately large) stems and a stout, swollen basal caudex (a rootstock that protrudes from the soil). The leaves are spirally arranged, clustered toward the tips of the shoots, simple entire, leathery in texture, 5–15 cm (2.0–5.9 in) long and 1–8 cm (0.39–3.15 in) broad. The flowers are tubular, 2–5 cm (0.79–1.97 in) long, with the outer portion 4–6 cm (1.6–2.4 in) diameter with five petals, resembling those of other related genera such as Plumeria and Nerium. The flowers tend to be red and pink, often with a whitish blush outward of the throat.
Flowers and leaves, ThailandPaired, follicular fruits on cultivated specimen, BengalSingle, dehiscent fruit showing seeds equipped with double pappus (tuft of hairs at both ends)Single seed 1 cm (0.39 in) long with pappusSeed 1 cm (0.39 in) long, stripped of the double pappus which allows wind-dispersalSeedling, 18 days old, 3.3 cm (1.3 in)
Adenium obesum subsp. swazicum (Eswatini, South Africa)
Adenium swazicum is a critically endangered African species native to Eswatini and Mozambique, growing up to 0.7 m (2.29 ft) tall.
Adenium somalense is also native to Africa, inhabiting Tanzania, Kenya, and Somalia, and reaching heights of 5 m (16.40 ft), which makes it the largest of these four subspecies.
Adenium socotranum is native exclusively to the island of Socotra, and can grow to be 4.6 m (15 ft), but despite its small range, it is of least concern regarding endangerment.
Adenium oleifolium is near threatened in the wild and is the smallest of these subspecies, growing at the tallest to 0.4 m (1.31 ft).
Adenium obesum produces a sap in its roots and stems that contains cardiac glycosides. This sap is used as arrow poison for hunting large game throughout much of Africa[6] and as a fish toxin.[7]
Adenium obesum is a popular houseplant and bonsai[8]intemperate regions. It requires a sunny location and a minimum indoor temperature in winter of 10 °C (50 °F). It thrives on a xeric watering regime as required by cacti. A. obesum is typically propagated by seed or stem cuttings. The numerous hybrids are propagated mainly by grafting on to seedling rootstock. While plants grown from seed are more likely to have the swollen caudex at a young age, with time many cutting-grown plants cannot be distinguished from seed-grown plants. Like many plants, Adenium obesum can also be propagated in vitro using plant tissue culture.[9]
