Castor: Sowing, planting and harvest calendar
When and how should you sow castor bean outdoors?
Sow castor bean, Ricinus communis, outdoors only after frost danger has passed and soil has warmed. Direct sowing needs enough warm season for development. In cooler climates, starting under cover gives more time. This is an ornamental crop: seeds are highly poisonous if swallowed and are not edible beans.
Choose a sunny, freely draining spot with room for the cultivar's mature spread. Avoid locations accessible to children or animals that may touch or eat seeds. Keep the packet closed and labelled, separate from food seeds. Wear gloves when handling the plant and wash your hands afterwards.
Weed and prepare fine soil without large clods. Place seeds at the depth specified for the lot, cover, firm gently and water without runoff. Maintain steady moisture during emergence without soaking the ground. Mark positions so you do not confuse seedlings with other crops. Thin later according to the stated mature size rather than retaining crowded plants. Do not break seeds or leave them scattered after sowing. Site choice must also account for later production of toxic seed capsules.
When and how should you plant a castor bean plant?
When does castor bean flower and how should you monitor flowering?
