Horsetail Oil: How to Make It and What It Honestly Does
Horsetail oil is a carrier oil infused with dried horsetail, and it is a genuinely good home made conditioning oil: it adds slip, softens the ends and cuts the friction that causes breakage. What it is not is a growth remedy. Horsetail is rich in silica, but the evidence that applying it to the scalp changes hair density is thin. Make it for shine and condition, not for miracles.
The silica argument, stated honestly
Horsetail contains more silica than almost any other common plant, and silica is a real component of connective tissue. The leap people make is from that fact to the conclusion that rubbing silica rich oil on a scalp grows hair. That leap is not supported. The European Medicines Agency lists horsetail as a traditional herbal preparation, meaning long standing use rather than demonstrated effect.
Key takeaways
- Horsetail oil is a real, simple infusion you can make at home with dried herb and a carrier oil.
- Use dried horsetail, never fresh. Water in the jar is how an infused oil grows mould.
- Its honest benefits are slip, softness and less friction breakage. Be sceptical of any claim that it grows hair.
- Keep the herb fully submerged, strain properly, store in dark glass and use within about six months.
- Patch test before first use, and never drink horsetail preparations. Speak to your GP first if you are pregnant, breastfeeding or taking any medicine.
What is horsetail oil?
An infused oil is not pressed from the plant the way olive or coconut oil is pressed from its source. It is an infusion: dried Equisetum arvense steeped in a carrier oil until some of the plant compounds transfer across. That distinction matters, because it sets a ceiling on how concentrated the result can be. You are making a gently scented, lightly enriched carrier oil, not an essential oil or an extract.
The carrier you choose does most of the practical work. Coconut oil is the one with the best evidence for reducing protein loss during washing, and it suits coarse or textured hair. Jojoba is light and closest to the scalp's own sebum, so it suits fine hair and anyone whose scalp objects to heavier oils. Olive oil is cheap, effective and heavy, which is fine for a pre wash treatment on dry ends but too much for leaving in.
What does the evidence actually say about horsetail?
Less than the marketing implies, and being straight about that is more useful than pretending otherwise. Horsetail is registered in Europe as a traditional herbal medicinal product, a category that rests on a long history of use rather than on trials showing an effect. The silica content is real and well documented. What is missing is evidence that silica applied topically in an infused oil reaches the follicle in a meaningful amount or changes what the follicle does.
There is a separate and weaker claim that oral silica supports hair strength. The studies most often cited for that are small, industry funded and use standardised silicon compounds rather than a home made horsetail oil, so they cannot be used to support a kitchen infusion. Where good sources disagree here, the disagreement is mostly between herbal tradition and clinical evidence, and we think readers deserve to be told which is which.
What it demonstrably does is what any well made hair oil does. It coats the fibre, reduces the friction of combing and styling, improves shine and helps hair hold moisture. Those are cosmetic effects and they are worth having. Our honest comparison of rice oil and rice water applies the same standard to another popular DIY, if you want to see how the two stack up.
How do you make horsetail oil at home?
The method is simple and the failure points are few. Use roughly one part dried horsetail to two parts carrier oil by volume, and make sure the herb stays completely submerged throughout, because anything above the oil line will spoil.
| Step | What to do | Why it matters |
|---|---|---|
| 1. Choose the herb | Dried Equisetum arvense only, from a reputable supplier | Fresh plant carries water, and water in oil grows mould and bacteria |
| 2. Sterilise | A clean, completely dry glass jar with a tight lid | Residual water from washing up is the most common cause of a spoiled batch |
| 3. Combine | One part herb to two parts carrier oil, herb fully covered | Exposed plant matter above the oil line is where spoilage starts |
| 4. Infuse, slow | Cool, dark spot for four to six weeks, shake every few days | Gentle and thorough. This is the method that gives the best result |
| 5. Infuse, quick | Double boiler on low for two to three hours, never hot enough to sizzle | Faster, but overheating degrades the oil and can turn it bitter |
| 6. Strain | Through muslin, squeezing the herb out | Any leftover plant matter shortens shelf life considerably |
| 7. Store | Dark glass bottle, cool, out of sunlight, use within six months | Light and heat oxidise oils. Discard if it smells sharp or rancid |
The slow method genuinely produces a better oil than the quick one. Heat speeds the transfer of plant compounds but also accelerates oxidation of the carrier, so a batch rushed through a double boiler tends to go off sooner. If you are impatient, the compromise most people are happiest with is a warm infusion held well below frying temperature for a couple of hours, then a fortnight in the cupboard before straining.
How should you use horsetail oil on your hair?
As a pre wash conditioning oil, principally. Massage a small amount of the oil into the scalp and through the mid lengths and ends, leave it for thirty minutes or overnight on the lengths, then shampoo it out. Used this way the oil reduces the swelling and drying that happens during washing, which is where a lot of everyday fibre damage originates.
| How to use it | Amount | How often |
|---|---|---|
| Pre wash scalp and lengths treatment | A teaspoon for short hair, a tablespoon for long | Once or twice a week |
| Overnight mask on the mid lengths and ends only | Enough to coat, not saturate | Weekly, on a towel over the pillow |
| Blended into a mask with yoghurt or avocado | A teaspoon into the mixture | Weekly |
| A few drops smoothed onto damp ends | Two or three drops, warmed in the palms | Daily if your ends are dry |
| Scalp massage before washing | A few drops, fingertips not nails | Once or twice a week |
Two practical warnings. Fine hair goes limp quickly, so keep the oil off the roots and treat it as an ends product. And oil is far easier to put on than to take off: apply less than you think you need, and if you do overdo it, shampoo the scalp twice rather than scrubbing harder.
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Is it hair loss, shedding or breakage?
This matters because the oil can genuinely help with one of these three and cannot touch the other two. Hair loss means the follicle has stopped producing, which shows as a defined patch or a widening parting, and no oil affects it. Shedding is the growth cycle releasing hairs that have finished their run, at fifty to a hundred a day, and each comes out full length with a small pale bulb; oil does not change that cycle either. Breakage is the fibre snapping mid length, leaving short pieces of uneven length with no bulb, and this is the one where a conditioning oil earns its place.
So if what you are seeing is dry, snapping, split ended hair that never seems to gain length, a conditioning infusion like this is a reasonable and inexpensive part of the answer. If you are seeing full length hairs coming out in quantity, or a parting that is widening, an oil is not the tool and our guides to telogen effluvium and why hair thins will point you at more useful ground.
Is horsetail oil safe to use?
For most people, applied to the scalp and hair, yes, with three genuine cautions. Patch test on the inner forearm before the first full use, because plant infusions are a common enough source of contact reactions. Do not take horsetail internally: the plant contains thiaminase, an enzyme that breaks down vitamin B1, and traditional preparations carry restrictions on internal use for that reason. And speak to your GP before using horsetail in any form if you are pregnant, breastfeeding, taking any regular medicine, or living with kidney problems.
Storage is the other safety point, and it is the one people neglect. An infused oil with plant matter left in it, kept warm and in the light, will spoil. Strain thoroughly, use dark glass, keep it cool, and throw it away if it smells sharp, sour or like old crayons. Six months is a sensible outer limit for a home batch.
What are the alternatives if you would rather not make it?
Making your own is cheap and satisfying, but it is not the only sensible route, and a shop bought product has consistency and a preservative system that a kitchen batch does not.
Grow More® Scalp Elixir
A ready made scalp serum if you want the massage step without the six week infusion and the shelf life problem. It goes onto the scalp rather than down the lengths, so it does not weigh fine hair down.
Masque Me® Hair Growth Mask
For the breakage side, a weekly mask does more for dry, snapping ends than an oil alone. Mid lengths and ends, once a week, rinsed out thoroughly.
Whichever you use, you still have to wash it out properly. A sulphate free shampoo removes an oil treatment without stripping the scalp, and our explainer on sulphate free shampoo covers why that balance matters. Watermans products are vegan, made in the UK, and part of a range with over 5 million bottles sold since 2012.
Watermans products are 100% cosmetic and do not treat medical hair loss. Individual results may vary.
Frequently asked questions
Does horsetail oil grow hair?
There is no good evidence that it does. Horsetail is high in silica and has a long history of traditional use, but neither of those establishes that an infused oil applied to the scalp changes hair density. Its honest value is cosmetic: slip, shine, softness and less friction breakage, all of which help you keep the length you already have.
How long does it take to work?
For the effects it genuinely delivers, immediately. Slip and shine are noticeable the first time you use it, and reduced breakage shows up over a few weeks as ends stop snapping. If you are waiting for new density, you will be waiting indefinitely, which is why setting expectations honestly at the start matters.
Can I use fresh horsetail instead of dried?
No, and this is the single most important rule of the method. Fresh plant material carries water, water trapped in oil creates the conditions for mould and bacterial growth, and a spoiled infused oil is not something you want on your scalp. Dried herb, dry jar, herb kept fully submerged.
How long does a home made batch last?
Around six months if you strain it thoroughly, bottle it in dark glass and keep it cool and out of sunlight. Leftover plant matter and warmth both shorten that considerably. Trust your nose: a sharp, sour or crayon like smell means the carrier oil has oxidised and the batch should be thrown away.
Which carrier oil is best for a horsetail infusion?
It depends on your hair. Coconut has the best evidence for reducing protein loss during washing and suits coarse or textured hair. Jojoba is light and close to the scalp's own sebum, which makes it the better pick for fine hair. Olive is inexpensive and heavy, best kept to pre wash use on dry ends.
Can I leave the oil in my hair overnight?
On the mid lengths and ends, yes, with a towel on the pillow. Leaving a heavy oil on the scalp overnight every night is less advisable, because it can leave the scalp congested and uncomfortable. Once a week overnight, or thirty minutes before washing, covers most of the benefit.
Is an infused herbal oil safe on colour treated hair?
Generally yes, and it can help colour treated hair, which is usually drier and more porous. Oil applied before shampooing reduces the swelling that washing causes. Do a strand test if your colour is fresh, since any oil can very slightly affect how light shades read.
Can I drink horsetail tea for my hair instead?
We would not suggest it on the strength of a hair claim. Horsetail contains thiaminase, which breaks down vitamin B1, and traditional herbal registrations carry restrictions on internal use as a result. If you are considering any oral herbal preparation, speak to your GP or a pharmacist first, particularly alongside other medicines.
Sources and References
- European Medicines Agency, Equiseti herba (horsetail) herbal monograph, on traditional use status and restrictions on internal use.
- StatPearls, NCBI Bookshelf, Physiology, Hair, on hair fibre structure and the growth cycle.
- NHS, Hair loss, on distinguishing ordinary shedding from causes that need medical input.
- British Association of Dermatologists, Telogen effluvium leaflet, on diffuse shedding and its triggers.
The short version
Horsetail oil is a dried herb infused into a carrier oil, easy to make, cheap, and genuinely useful as a conditioning and anti breakage treatment. Use dried herb in a dry jar, keep it submerged, infuse slowly for four to six weeks, strain well and store it in dark glass for no more than six months. Use it before washing rather than as a leave in, keep it off fine roots, and patch test first. Judge it on shine, softness and ends that stop snapping, and be sceptical of anyone selling it as a growth remedy.
