Ricinus communis- Castor bean -annual- Height 6-10 feet; Blooms June to October; Full sun; Water; dry to medium.  Ricin, plant&#x27;s active ingredient, is poisonour and can be fatal in small doses.  Seeds are released explosively, thus seedinling may arise a long way from a mother plant. Castor oil can be extracted from the seeds and is not toxic.