castor oil plant

I 'think' you mean Fatsia Japonica rather than Ricinus Communis which is an annual

Ricinus makes a fantastic 'dot plant' in any mixed planting. as mg says it is an annual but the amount of growth it puts on in a year is stunning. our local council use them in summer bedding on the roundabouts.
i am sure you know all parts of the plant are toxic if eaten.