The bold look is back in garden design, so not surprisingly, castor beans have reappeared as backdrops for gardeners wanting to make a prominent statement in their plantings. Everything about castor bean is bold and a bit audacious, so gardeners with a bit of maverick in them seem to be drawn to this big plant. Castor bean is a flowering plant that belongs to the spurge family. It originates from eastern Africa, but it can be found in warm, tropical areas around the world today. Castor bean grows on fertile, well-drained soil in areas that provide sufficient moisture and sun. Castor bean has erect stem that can reach 6 to 15 feet in height. People cultivate castor bean as a source of oil that has application in various industries. Several varieties of castor bean are cultivated for ornamental purposes.