Castor oil plant
Castor oil plant - Ricinus communis - is most well known for the extreme toxicity of its seeds, which contain ricin, a poison 200 times more deadly than cyanide. the remainder of the plant is still toxic, but less so. Clearly this plant should not be grown where there is the slightest risk of small children getting hold of the seeds.
It also, not surprisingly, contains castor oil in the seeds, and is used for various medicinal purposes.
Dangers apart, it is a fine plant. In tropical and sub-tropical regions it grows as a tree, to about 12 metres height, but in more temperate climates it grows as an annual, rapidly reaching up to two metres in height. The bright pink-purple flowers are also very dramatic, and last into early autumn.
It grows best on a well drained soil, and likes full sun. It is easy to grow from seed, and also self-seeds very easily.
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