 Castor beans grow in temperate to tropical climates but are not resilient against frost. They demonstrate best yields if temperatures are high throughout the year. Although natively coming from Africa it now grows pretty much everywhere in tropical and subtropical regions. Castor oil is used as high grade lubricant for the aeronautical industry and top end machineries.Yields are considered to be good for energy but not as good as Palm fruit and Jatropha. If the crops are under irrigation seed yields average 900 to 1100 kg/ha, but do drop dramatically without irrigation on dry soils. Oil content varies from 35% to 55%, suggesting an oil yield at a maximum of 605 kg/ha. Harvesting can be done mechanically though in the less developed countries the fruits are collected by hand picking. The oil and the remaining oil cake is non-edible and is highly toxic. Farmers need to take into account that feedstock crops should not be planted near castor fields as contamination of harvests with castorseeds may render entire harvests worthless! Source: James A. Duke. 1983. Handbook of Energy Crops. | 
