Rowan & Thistle

PLATE No. 016

Ingredient Collection

Castor Oil

Ricinus communis

Botanical plate of Castor (Ricinus communis): a red-stemmed branch with large, deeply lobed leaves and spiny green and red seed capsules, beside a flowering spike, a green capsule, a dried red capsule, a split capsule showing mottled seeds, and a golden drop of oil.

Figure Key

  • Fig. 1 Leafy branch, in flower and fruit
  • Fig. 2 Flowering spike
  • Fig. 3 Immature seed capsule
  • Fig. 4 Mature seed capsule
  • Fig. 5 Split seed capsule
  • Fig. 6 Castor oil

The Ingredient

Castor oil begins inside the plant's distinctive spiny seed capsules. As the capsules mature and dry, they split to reveal beautifully mottled seeds rich in oil. The oil pressed from those seeds is unusually thick compared with most plant oils. Much of that distinctive texture comes from ricinoleic acid, a naturally occurring fatty acid that makes up most of castor oil and helps give it its characteristic richness, slip, and gloss.

From Plant to Ingredient

  1. Castor Oil, step 1 — Castor Seed Capsule: a green castor seed capsule covered in soft spines.

    1. Castor Seed Capsule

    The plant develops distinctive spiny capsules that hold the seeds.

  2. Castor Oil, step 2 — Mature Seed Capsule: a dried red-brown castor capsule bristling with spines.

    2. Mature Seed Capsule

    As it matures, the capsule dries and changes from green to deep reddish brown.

  3. Castor Oil, step 3 — Castor Seeds: a castor capsule split open to show three mottled gray-and-cream seeds.

    3. Castor Seeds

    The mature capsule splits open to reveal the mottled, oil-rich seeds.

  4. Castor Oil, step 4 — Castor Oil: a single thick golden-brown drop of oil.

    4. Castor Oil

    The seeds yield the exceptionally rich, viscous oil used in our formulas.

Why We Chose It

Castor oil behaves differently from many of the lighter oils in our Herbarium. Its naturally thick texture provides exceptional slip, cushion, and staying power, helping skin and hair feel deeply conditioned. It also lends a smooth, substantial feel to products where a lighter oil simply wouldn't do the same job.

What You'll Notice

  • Rich Conditioning — Leaves dry-feeling skin and hair feeling softer and well conditioned.
  • Exceptional Slip — Its naturally thick texture provides smooth glide and cushion
  • Gloss & Shine — Helps give hair and lips a smooth, glossy appearance.
  • Lasting Feel — Provides substantial conditioning that doesn't disappear as quickly as lighter oils.

Botanical Profile

Scientific Name
Ricinus communis
INCI Name
Ricinus Communis (Castor) Seed Oil
Plant Part Used
Seed
Final Ingredient
Oil
Origin
India

A Closer Look

Castor oil is unusual among common plant oils because nearly 90% of its fatty acids are typically ricinoleic acid. A fatty acid is simply one of the natural building blocks that makes up an oil. Ricinoleic acid has a slightly different structure than the fatty acids found in many other plant oils, helping explain castor oil's unmistakably thick texture and substantial feel.

Products Featuring Castor Oil Featured In

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