A widespread weed in South Africa, Datura, grows mainly in places where the soil has been disturbed, such as along roadsides, seasonal river courses, as well as in cultivated lands. We grew up knowing it by the Afrikaans name of Stinkblaar (Stinking Leaves) although I later discovered its English common name is Thorn Apple – at least two varieties commonly occur here: the Large Thorn Apple (Datura ferox) – also known as the Fierce Thorn Apple – and the Common Thorn Apple (Datura stramonium). I find it interesting that the Afrikaans name focuses on the leaves (which produce an unpleasant smell when crushed), while the English name points to the fruit. The genus name Datura comes from the Bengali name ‘dhatura’ for the plant, while the species name ferox means ‘strongly fortified’ and refers to the long spines on seed pods. The seeds of both are poisonous, so it was a plant we were warned from early on to avoid.
The spiny fruit houses the highly toxic kidney-shaped seeds. The photograph below shows the green fruit. This later hardens and dries to a dark brown before splitting open to reveal the black seeds. The Common Thorn Apple is also known colloquially in this country as malpitte (crazy seeds). All parts of Datura plants are poisonous and may prove fatal if ingested by humans as well as livestock and pets as they affect the central nervous system.
The white to creamy-coloured flowers are trumpet-shaped. The petals sometimes show a violet tinge.
This annual belongs to the Solanaceae – or deadly nightshade – family. Although these plants have become naturalised over most tropical and warm temperate regions, they are thought to have originated from the tropical regions of Central and South America. Datura stramonium is one of the world’s most widespread poisonous weeds and it competes aggressively with crops in the field and pasture. It is listed as a noxious weed in South Africa.