Castor Oil for Nails: How to Use It (and What It Won't Do)

Castor oil is the cheapest, most boring and most effective thing you can put on dry nails. It won't make them grow twice as fast, whatever social media says, but used every evening it keeps the nail plate supple so it bends instead of splitting.

Why castor oil works on nails

Castor oil is unusually thick and rich in ricinoleic acid. It stays on the nail and the skin around it longer than lighter oils, forming a film that slows water loss overnight. Supple layers are layers that don't separate, which is exactly what peeling nails need.

How to use it

• When: every evening, after the last hand wash.
• How much: one drop per nail, two if your nails are very dry or peeling.
• How: massage the drop into the nail and the cuticle for about a minute. The massage matters as much as the oil.
• Bonus: once or twice a week, sleep in thin cotton gloves after applying it.

Pure, cold-pressed castor oil in a dropper bottle is all you need. If you find it too sticky, mix it half and half with jojoba oil.

What to expect

After one week, cuticles look smoother. After three to four weeks, the new nail growing out from the cuticle is visibly less prone to splitting at the tip. The old, damaged part will only disappear as it grows out and you file it off, which is why patience and short nails go together.

What castor oil won't do

• It won't make nails grow dramatically faster. Growth speed is set by the matrix, not by what you put on top.
• It won't fix discoloration, a dark band or a nail lifting from its bed. Those deserve a dermatologist's look.
• It doesn't replace gloves: if your hands spend the day in water, start there. See brittle, peeling nails: 7 home fixes.

Is it right for your nails?

Not every nail needs the same thing. The Nails Paris app reads your nails from a photo of each hand and tells you whether castor oil, jojoba, shea or simply a different filing habit should come first, with a routine you can follow every evening.