Castor Oil Plant

Africa, Asia

General description

Suckering perennial shrub or small tree < 4 m tall. Stems are hollow, branching and hairless. Leaves are large, alternate, glossy green/red/purple/brown, palmate and serrated. Flowers are red/green and borne in inflorescences. Seed capsules are spherical, greenish and spiny.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell castor oil plant within the Auckland region.
  • You must not plant castor oil plant within the Auckland region, unless you are transferring an existing plant on your land to another location within the boundaries of the same property.
  • You must destroy any castor oil plant on land that you occupy if it has been planted in breach of the above rules and you are directed to do so by an authorised person.

Open habitats, disturbed sites, wasteland, riparian margins, gardens.

Seeds dispersed by explosive dehiscence and water. Vegetative spread from adventitious shoots.

May outcompete and prevent revegetation of plants in disturbed habitats, pasture and cleared forestry plantations. Extremely poisonous to humans, livestock, native fauna and pets. Strongly allergenic.

Site Management

Follow up treated areas 3 times per year. Encourage natural regeneration of native plants or replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.

Recommended approaches

Physical control

Method: Dig out

Plant parts requiring disposal: Seeds

Disposal options: Remove to greenwaste or landfill if practical


Biocontrol is currently not available for this species.

Community agrichemical control recommendations

No qualifications
Cut stump and paste freshly cut base of stems with double strength glyphosate gel
Cut stump and spray freshly cut base with 200ml glyphosate green per 1L of water

Certified Handler/Experienced agrichemical user
Foliar spray with 200ml glyphosate green per 10L of water and 20ml penetrant

Safety notes

Extremely poisonous, especially seeds

CAUTION: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.

Similar species

Fatsia japonica

The leaves of fatsia are thicker & more leathery. Fatsia has round white flowers followed by black berries.

RPMP status

Whole region (Sustained Control)
Hauraki Gulf Controlled Area Notice pest
Castor oil plant - Main species image