11 Surprising Things You Can Do With Castor Oil (That Most People Never Think Of)

You probably already know about castor oil and hair. The thick, golden oil has become a cult favourite for brows, lashes, and scalp health. And yes, it works brilliantly for all of that.

But here’s the thing. Most people buy a bottle, dab a little on their eyebrows every night, and then let the rest of it sit in a drawer for three years. That’s a terrible waste of one of the most versatile natural oils you can own.

Castor oil comes from the seeds of Ricinus communis, a plant native to India and East Africa. It’s around 90% ricinoleic acid, a rare fatty acid that gives it exceptional viscosity, a long shelf life, and genuinely useful properties for skin, hair, wood, metal, and more. It’s thick, slightly sticky, and almost odourless. It plays well with other oils. It doesn’t go rancid quickly. It’s affordable.

And it does a lot more than you might think.

These are the uses that rarely make it into the standard castor oil roundup. Some are beauty hacks. Some are home fixes. A few are just a bit clever.

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1. A splinter-drawing compress

Nobody talks about this one, and it’s genuinely useful.

Castor oil has been used in traditional folk medicine as a drawing agent, meaning it can help pull debris, splinters, and embedded matter closer to the skin’s surface. The ricinoleic acid is thought to soften the surrounding tissue and reduce inflammation, which makes removal much easier.

Apply a generous blob of castor oil directly over the splinter. Cover it with a plaster or piece of fabric tape. Leave it overnight. By morning, the splinter will often be sitting much closer to the surface, or have worked itself out entirely. No digging required.

This works for ingrown hairs too. Apply castor oil to the area, leave it covered for a few hours, and the trapped hair tends to surface more easily.

2. A DIY tinted lip gloss base

Castor oil is the backbone of almost every commercial lip gloss ever made. It’s no coincidence. The thickness gives gloss its body, the shine comes naturally from the oil itself, and it clings to lips without feeling heavy.

Making your own tinted lip gloss takes about five minutes. Melt 1 teaspoon of candelilla wax with 2 tablespoons of castor oil in a small heat-safe bowl over hot water. Stir in a tiny amount of natural lip-safe pigment (beetroot powder gives a gorgeous rose tint, cocoa powder for a nude). Add 2 drops of peppermint essential oil if you like a tingle. Pour into small lip gloss tubes and allow to set.

It takes a few tries to get the texture exactly where you want it. Less wax means glossier. More wax means thicker. Both are wonderful.

3. An overnight foot treatment that actually works

The skin on your heels is some of the thickest on your body. Most moisturisers just sit on top of it and do very little. Castor oil is different because its molecular weight allows it to penetrate deeper into thickened skin, and the ricinoleic acid softens keratin effectively.

Before bed, rub a generous amount of castor oil into your heels and the balls of your feet. Mix it with a little coconut oil if you find it too thick to spread. Put on a pair of old cotton socks and go to sleep. Do this three or four nights in a row and the difference is quite dramatic. For a brilliant natural add-on, this pairs well with your broader hydrating skincare ideas — just translate them south.

If you want to step things up, add a few drops of peppermint essential oil to the blend. It boosts circulation and feels incredible on tired feet.

4. A brow-shaping wax alternative

Tinted brow gels are expensive. Most of them contain synthetic polymers that can make brow hairs brittle over time. Castor oil is a very decent alternative, and it does double duty.

A tiny amount, applied with a clean spoolie, tames and shapes brow hairs just as well as a clear setting gel. The slight tackiness holds everything in place without going crunchy. And it conditions the hairs while it works. For naturally thin or sparse brows, the regular conditioning does seem to support healthier, stronger growth over time.

Use Jamaican black castor oil if you’re focused on the conditioning side, regular cold-pressed castor oil if you just want the hold. The Jamaican version has a slightly stronger smell but is often preferred for hair work because of the ash content, which raises the pH of the hair shaft slightly and may improve penetration.

5. Rust prevention for garden tools

This one is practical and a bit satisfying.

Metal garden tools rust when they’re exposed to moisture and left wet. A thin coat of oil creates a barrier that stops that from happening. Castor oil works well for this because it’s thick enough to stay put, it doesn’t go rancid quickly, and it’s non-toxic, which matters if your tools touch soil where you grow food.

After cleaning and drying your tools, rub a small amount of castor oil onto the metal parts with a cloth. Buff off the excess. Store the tools somewhere dry. That’s it. Do it at the start and end of the growing season. It also works on the metal parts of kitchen scissors, which tend to seize up over time.

6. Sticker and adhesive residue remover

Castor oil breaks down adhesives. It’s not the fastest method, but it’s gentle, chemical-free, and won’t damage most surfaces.

Apply a few drops directly onto the sticky residue left behind by a label or sticker. Let it sit for five to ten minutes. Then rub gently with a soft cloth. The adhesive lifts away cleanly. Finish by wiping the surface with a damp soapy cloth to remove the oil. It works on glass jars, ceramic, finished wood, and metal tins. Always do a small patch test on wood first, as untreated or unfinished wood can absorb the oil and darken slightly.

This is also brilliant for getting the residue off new jars you want to reuse for DIY beauty products.

7. A conditioning treatment for wooden cutting boards and utensils

Wooden kitchen items need oil. Without it, they dry out, crack, and eventually split. Most people reach for food-grade mineral oil, which is a petroleum by-product. Castor oil is a completely natural, plant-based alternative.

Apply a thin layer of castor oil to a clean, dry cutting board. Rub it in well with a cloth. Let it soak in for an hour, then wipe off the excess. For deeply dried-out boards, you may need to repeat this two or three times. The oil penetrates the wood, conditions it from within, and brings back the colour and sheen.

This also works on wooden spoons, salad servers, and any other wooden kitchen tools. Do it once a month and they’ll last indefinitely.

8. A natural soap additive for better lather

This one is more for anyone who makes their own cold-process or melt-and-pour soap. Adding castor oil at around 5 to 10% of your total oil weight does something genuinely useful: it increases the foam quality and helps create a creamier, more stable lather.

Castor oil is also one of the few carrier oils that boosts the bubbles produced by other oils in a soap recipe. It doesn’t saponify the same way as most oils because of its unusual fatty acid profile, which is what makes it so effective as a foam booster.

If you use castile soap rather than making your own, try adding a few drops of castor oil directly to your liquid soap dispenser. It makes the texture richer and the lather slightly creamier.

9. An elbow and knee treatment you leave on overnight

Elbows and knees are chronically neglected, and they show it. The skin there is thicker and tends to look darker due to the accumulation of dead skin cells and the general lack of moisture retention. Standard body lotions barely touch them.

Castor oil, applied overnight on its own or blended 50/50 with jojoba oil, makes a real difference if you’re consistent. Jojoba softens castor oil’s texture and is an excellent complement because it mimics skin’s natural sebum. The castor oil locks in moisture and softens the thick outer layer of skin over time.

Apply before bed, cover the elbows or knees with an old long-sleeved top or leggings, and let it work overnight. This fits neatly into a broader simple natural face routine approach, applied from head to toe.

10. A pre-shave or post-shave treatment for legs

Shaving creates micro-damage in the skin barrier. Most commercial shave gels contain a mix of synthetic thickeners and fragrances. Castor oil is an excellent pre-shave option because its viscosity gives the razor something to glide over, and the oil conditions the skin at the same time.

Apply a thin layer to wet legs before shaving. The razor moves smoothly, there’s no irritation, and you skip the need for a separate moisturiser afterwards because the oil has already done most of the work. It rinses off almost completely, leaving just enough to keep the skin soft.

For post-shave, mix a few drops with aloe vera gel to calm any redness or sensitivity. The combination is cooling, soothing, and genuinely effective. This pairs well with all the other ideas in our natural skin treatments guide.

11. A sleep ritual for stiff or achy joints

This is probably the least glamorous use on the list, and one of the most worthwhile.

Castor oil applied topically over stiff, achy, or inflamed joints has a long history in folk and Ayurvedic traditions. The ricinoleic acid in castor oil has demonstrated anti-inflammatory properties in studies, and while this isn’t a replacement for medical treatment, many people find regular topical application helpful for chronic joint stiffness, particularly in the hands, wrists, and knees.

Mix 1 tablespoon of castor oil with 3 drops of frankincense essential oil and 3 drops of lavender essential oil. Warm the blend slightly between your palms. Massage slowly into the joint for three to five minutes before bed. Cover with a cotton cloth if you like. The frankincense adds additional anti-inflammatory support, the lavender helps you wind down, and the ritual of the massage itself is genuinely calming.

Do this as part of your evening wind-down and it becomes less about joint pain and more about a moment of care.

A few things worth knowing about castor oil

Castor oil is thick, and that’s part of its power. But “thick” also means it can clog pores if applied liberally to the face, particularly for oily or combination skin types. Use it sparingly on the face, if at all, and always blend it with a lighter oil when using it there.

It’s also worth choosing cold-pressed, organic castor oil where possible. The quality varies enormously between brands, and the cold-pressed version retains more of the beneficial compounds.

Finally, patch test before any new application. It’s rare, but castor oil can occasionally cause a mild allergic reaction in sensitive individuals.

References

1. Vieira C, Evangelista S, Cirillo R, Lippi A, Maggi CA, Manzini S. Effect of ricinoleic acid in acute and subchronic experimental models of inflammation. Mediators Inflamm. 2000;9(5):223-228.
2. Tunaru S, Althoff TF, Nusing RM, Diener M, Offermanns S. Castor oil induces laxation and uterus contraction via ricinoleic acid activating prostaglandin EP3 receptors. Proc Natl Acad Sci USA. 2012;109(23):9179-9184.
3. Marwat SK, Rehman F, Khan EA, Baloch MS, Sadiq M, Ullah I, et al. Review: medicinal uses and pharmacological activities of Ricinus communis L. Pakistan J Biol Sci. 2017;20(1):1-8.
4. Boddu SH, Bhagav P, Karla PK, Jacob S, Adatiya T, Maniar K, et al. Novel drug delivery strategies for the treatment of skin disorders. Curr Drug Targets. 2019;20(13):1359-1374.
5. Patel VR, Dumancas GG, Viswanath LCK, Maples R, Subong BJJ. Castor oil: properties, uses, and optimization of processing parameters in commercial production. Lipid Insights. 2016;9:1-12.