Ricinus communis 

(ri' chi' nuss co-muu' niss)

Common name: Caster Bean, Castor Oil Plant

Family: Euphorbiaceae (Spurge)

Height x width: 5-10' x 5-10' (to 40' high in native habitats)

Growth habit: upright, branched

Growth rate: rapid

Foliage: alternate, large to 3' across but generally 1' across, palmately 5-11 lobed, lobes ovate to lanceolate and serrate; many colors but generally variation on red

Flowers: monoecious, not significant, no petals, in axillary panicles; fruit are about one inch, smooth or spiny

Hardiness: USDA zone 9

Soil: well drained, fertile

Light: sun

Pests and Problems: spider mites when young indoors; spindly and smaller leaves, more flowers, on poor soil and less fertility, and shade

Landscape habit, uses: specimen for size and foliage color, back of borders;

Other interest: foliage contact may cause irritation, all parts especially the seeds are poisonous if ingested; seeds are used for an oil, in turn used medicinally and in soap, paints and varnishes; genus from Latin ricinus for tick, which seeds resemble; native from N.E. Africa to Western Asia; naturalized on wastelands such as along roads and stony slopes in warm climates

Other culture: usually too large for containers and easily and quickly grown from seed so generally not overwintered; may need staking if on exposed and windy sites; very frost sensitive

Propagation: seeds sown directly, or shortly before planting out in the north

Species: only this one in the genus

Cultivars: there are only a few cultivars, these being the main ones, and it is often found as simply the species
Cultivar foliage other
'Carmencita' maroon rose red seed pods, RHS award
'Carmencita Pink' maroon pink seed pods
'Gibsonii' dark red compact 4-5'
'Impala' dark red compact 4-5', young growth carmine
'Sanguineus' blood red stems red also
'Zanzibarensis' green, white veins tall 6-10'

©Authored by Dr. Leonard Perry, Professor, University of Vermont as part of PSS123 course.

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