Description

Castor bean plant or castor oil plant is a species of perennial flowering plant  in the spurge   family, Euphorbiaceae. It is the sole species in the monotypic genus , Ricinus, and subtribe, Ricininae. The evolution of castor and its relation to other species are currently being studied using modern genetic tools. Its seed is the castor bean, which, despite its name, is not a bean(that is, the seed of many Fabaceae). Castor is indigenous to the southeastern Mediterranean Basin, Eastern Africa, and India, but is widespread throughout tropical regions (and widely grown elsewhere as an ornamental plant). The castor bean plant, an erect, tropical shrub or small tree, grows up to 30 feet tall. As an annual in the cooler zones, it grows up to 15' tall. It is a very fast growing plant. The joints of the hollow stem, stalks and leaves are reddish to purple. The 6 - 11 lobed, palmate leaves with uneven serrated edge, are also red or colored and often have a blue-gray bloom. There is also a green variety. The flat seeds are in a seedpod that explodes when ripen. All the top of the stem and stalks are the inflorescence with the male - and female flowers. The female flowers are the fuzzy red structures at the top of the flower spike with the male flowers positioned on the lower half, and have conspicuous yellow anthers The oblong fruit turns brown when ripe. In each seed pod (a capsule) there are three seeds. The seeds of castor bean or castor oil plant, are very poisonous to people, animals and insects; just one milligram of ricin (one of the main toxic proteins in the plant) can kill an adult. The castor oil is extracted from the beans, which is used for medicinal purposes. Commercially prepared castor oil contains none of the toxin.

Characteristics:

Castor bean plant can vary greatly in its growth habit and appearance. The variability has been increased by breeders who have selected a range of cultivars for leaf and flower colors, and for oil production. It is a fast-growing, suckering shrub that can reach the size of a small tree, around 12 m (39 ft), but it is not cold hardly. The glossy leaves are 15–45 cm (6–18 in) long, long-stalked, alternate and palmate with five to twelve deep lobes with coarsely toothed segments. In some varieties they start off dark reddish purple or bronze when young, gradually changing to a dark green, sometimes with a reddish tinge, as they mature. The leaves of some other varieties are green practically from the start, whereas in yet others a pigment masks the green color of all the chlorophyll-bearing parts, leaves, stems and young fruit, so that they remain a dramatic purple-to-reddish-brown throughout the life of the plant. Plants with the dark leaves can be found growing next to those with green leaves, so there is most likely only a single gene controlling the production of the pigment in some varieties. The stems and the spherical, spiny seed capsules also vary in pigmentation. The fruit capsules of some varieties are more showy than the flowers. The flowers lack petals and are unisexual (male and female) where both types are borne on the same plant in terminal panicle-like inflorescences of green or, in some varieties, shades of red. The male flowers are numerous, yellowish-green with prominent creamy stamens; the female flowers, borne at the tips of the spikes, lie within the immature spiny capsules, are relatively few in number and have prominent red stigmas.

Medicinal Uses:

An alcoholic extract of the leaf was shown, in lab rats, to protect the liver from damage from certain poisons. In Manipur, leaves are warmed, crushed and applied to annus as a remedy for bleeding piles. Seed oil is purgative. Leaf-paste is used as poultice on sores, gout or rheumatic swellings. Decoction of root is given in lumbago. For lactation, leaves of the plant are heated and applied to a woman's breasts to improve secretion of milk.