A many branched annual to perennial shrub or small tree to 3 metres tall with stalked, large leaves with 5-9 finger like lobes and softly spiny capsules. It has yellow male flowers below the reddish female flowers from spring to autumn.
As A Soil Indicator:
Low Calcium, Very low Potassium, Very high phosphate, Very high Magnesium, High Manganese, High Iron, High Sodium, High Copper, Very little organic matter. 
Life cycle:
Annual biennial or perennial. Germinates from autumn to spring and grows quickly. They may reach a height of several metres in their first year. Flowers from August-March depending on the area. Seed may be set in the first year. Growth slows or the plants die in winter. Surviving plants commence rapid growth in spring. It behaves as an annual in frosty areas.
Castor oil extracted from the seeds for a lubricant and hydraulic fluids because its viscosity is stable as temperature increases.
Seeds contain ricin and are poisonous to stock and poultry and humans. Seeds are very toxic to humans and 6-8 seeds may cause death.
Seeds produce an allergic reaction in skin. Cases of poisoning in the field are rare. Horses are most sensitive followed by sheep, cattle and pigs and poultry are the least sensitive. Seeds and oil can be made safe by heating to 500C or more.

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