Ricinus communis, the castorbean or castor-oil-plant, is a species of flowering plant in the spurge family, euphorbiaceae. It is the sole species in the monotypic genus, ricinus, and subtribe, ricininae. Common name castor bean .Bloom time june to october . Height 6.00 To 10.00 Feet . Difficulty level easy to grow . Planting care - before you plant, be sure that you choose varieties proven in your climate. When in doubt, all-america rose selections winners are good bets. Or check with your local nursery.If you order plants from a mail-order company, order early, in january or february (march at the latest). Sunlight full sun soil well-drained soil water dry to medium temprature 10-18c fertilizer apply any organic fertilizer care also, select a site that gets full sun. For dependable blooms, plants need six to eight hours of direct sunlight a day. If its too shady, the stems will attempt to lean towards the sun or get spindly and fall over. Most of the popular varieties prefer acidic to neutral soil, but some are lime-tolerant or prefer alkaline soils. Care plants love waterbut dont drown them. That is, they dont like to sit in water, and theyll die if the soil is too wet in winter. The ideal soil is rich and loose, with good drainage. One of the worst mistakes you can make is to not provide adequate drainage. Use mulch. Special feature shrubby annual. Specimen. Containers. Use medicinal use ricinus communis, the castorbean or castor-oil-plant, is a species of flowering plant in the spurge family, euphorbiaceae. The seed also contains ricin, a water-soluble toxin, which is also present in lower concentrations throughout the plant.