Hardy in USDA Hardiness Zones 8-11, castor-beans can become noxious self-seeding annuals
that are difficult to control even in colder zones. The deep red capsule shown here (inset) holds
three seeds. The seed coats contain a poison called ricin, as little as one milligram can kill an adult. Therefore, it is strongly suggested that this plant is kept away from children. Castor oil is pressed
from the seed and used to make a variety of products; medicines, paints, lamp oil, and varnishes.
You can view this castor-bean in the National Herb Garden.