About Castor Bean Plants

Geography

• Although the castor bean plant is native to tropical east Africa, this valuable plant can now be found in warm and temperate climates throughout the world. They are particularly prevalent along stream and river banks, or wherever the soil stays well-drained. By the turn of the twenty-first century, as much as a million tons of castor beans were being produced globally per year. The top three producers were India, China and Brazil.

Identification

• The scientific name for the castor bean plant, Ricinus communis, has an unexpected backstory. The Latin word "ricinus" means "tick": the seeds of the castor bean plant were originally thought to resemble the common parasite after they had fully engorged on blood. The plant itself can reach 10 feet in height in a single season, and its long-stalked, alternate leaves can be 6 to 18 inches long. The leaves are glossy and coarsely toothed, vary in color from dark green to reddish purple, sport 5 to 12 lobes and produce clusters of spiny, green fruit.

History

• Castor beans have been found in Egyptian tombs, which date back to as long ago as 4000 B.C., and references to the medical uses of the plant can be found in the 3,500-year-old Ebers Papyrus. Ancient Greek philosophers remarked on how oil from the castor plant cold be used for everything from lighting to hair growth. Even up until the twentieth century, castor oil was widely used as convenient and low-cost purgative and laxative.

Benefits

• Castor oil is the key component in numerous industrial applications. Its impressive water-resistance has made it an essential component for the paint and varnish industry. The application of castor oil can maintain viscosity at extremely high temperatures, which has given rise to Castor motor oil. Castor oil is even essential to nylon production; every ton of nylon requires 3 tons of castor oil. And when not harvested, the plant is a common sight in gardens, even thought the plant is rich with a deadly toxin known as ricin.

Warning

• In 1978, a dissident Bulgarian journalist was assassinated with a BB pellet that had been packed with poison. The entire castor bean plant produces ricin, one milligram of which can kill an adult. Ricin is particularly prevalent in the castor bean, whose eye-catching color can prove tempting to children. Some gardeners go so far as to cut off the plant's flowers to prevent seed production. Despite its potency, however, ricin poisoning remains relatively rare.