Ricinus communis L.

Habitat

Terrestrial

Madagascar: Ricinus communis flowers as early as the middle of the wet season.
Mayotte: R. communis flowers from April to September and fruits from May to November.
New Caledonia: The development cycle of Ricinus communis is very fast. Flowering can occur at the end of December and spread over the rainy season, followed by fruiting from May.

Ricinus communis grows on sandy river beds, forest margins, disturbed areas and riverine thickets.

Madagascar: Ricinus communis grows on ferruginous soils, and fairly rich alluvial soils, along paths and around inhabited areas, in sunny places. It is a weed in fallows and at the edge of crops up to 1500 m altitude, in semi-intensive maize or cassava-based cropping systems, in semi-arid South and Southwest regions, Highlands, Middle West (subhumid).
Mayotte: R. communis is an exotic species commonly naturalized in secondarized and open environments, villages, wastelands, crops and pastures. It is sometimes cultivated for ornamental purposes.
New Caledonia: It grows mainly along rivers and creeks and from these places of infestation it can spread on neighboring pastures.
Reunion: Primarily a ruderal species present at the edge of the fields, sometimes in sugarcane fields at low altitude.
South Africa: Coastal regions of South Africa as well as Gauteng and Limpopo province. Occurs throughout KNP.

Global harmfulness

Ricinus communis is one of 300 major invasive species in tropical Australia, the Indian Ocean and Oceania, including New Caledonia,

Local harmfulness

Madagascar: Ricinus communis is an infrequent and no abundant weed species in crops. It can be locally abundant on the edge of the canals, in the fallow land and around the inhabited places. It is relatively more common in areas of cultivation of semi-arid South and Southwest semi-arid soil (associated cropping system of maize, cassava and legumes).
New Caledonia:  It was introduced in the mid-19th century. It frequently invades the banks of rivers and creeks and from these places of infestation it can spread on the surrounding pastures, but never abundant in the fields.
Réunion: Scarce weedt (4% of crop fields) and rarely abundant in sugarcane fields and cabbages. When poorly managed, it can grow as a strong population. Rather a ruderal species.
South Africa: It is a common weed that occasionally occurs in perennial crops such as sugarcane. It is declared as an invasive plant with a commercial value. It competes with native pioneer species, particularly in watercourses.

Medicinal: Seeds of Ricinus communis are used to produce castor oil widely used as a cosmetic product and to treat many diseases. The seeds are very toxic, used as a laxative. The leaves and roots are used in medicine against headaches and rheumatism. The poultice of fresh leaves is used against hemorrhoids.
Other: Seeds are also used in witchcraft.

Herbarium pictures ReCOLNAT: https://explore.recolnat.org/search/botanique/simplequery=Ricinus%2520communis