November 10, 2026

Rosemary, Castor and Pumpkin Seed Oil: Your Plant-Powered Hair Ritual

Rosemary oil has gone from kitchen herb to the most talked-about hair ingredient online. Much of that buzz traces back to one small 2015 study that compared it with minoxidil, the hair-loss medicine. Here is what that research did and didn't show, why minoxidil carries a little-known risk to cats, and how a plant-powered oil fits into a healthy hair routine.

We also cover why we blended rosemary with Black Jamaican castor oil and pumpkin seed oil in Get to the Root, how to use a hair oil for the best results, and how to keep pets safe around anything you put on your scalp.

Minoxidil: effective, but not risk-free

Minoxidil is a licensed hair-loss medicine, sold over the counter as a liquid or foam (best known as Rogaine or Regaine). It was originally a blood-pressure drug: it widens blood vessels, and on the scalp that is thought to boost blood flow to follicles and keep them in their growth phase longer. It works for many people, but it has to be used every day, indefinitely, and common side effects include scalp itching, irritation and flaking.

The hidden danger to cats and dogs

The risk most users never hear about is to their pets. In May 2026 the UK charity Cats Protection warned that 20 cat poisonings from minoxidil had been recorded by the Veterinary Poisons Information Service in a year, and that the true number is likely higher. Minoxidil can cause a dangerous drop in blood pressure in cats, fluid on the lungs, breathing difficulty and collapse.

The numbers are stark. A 2025 review cited by the American Academy of Dermatology found 97.8% of exposed cats and dogs ended up in hospital, and 10 of 68 cats died. A few drops on a cat's coat is enough.

Most poisonings are not from pets raiding the bathroom cabinet. They happen through everyday contact:

a cat licking freshly treated skin or hair
grooming residue off its own fur after a cuddle
sleeping on a pillow or bedding with minoxidil on it
chewing a used tissue, applicator or empty bottle

If you use minoxidil and share your home with a cat, none of this means you must stop. It does mean strict habits: apply it away from pets, let it dry fully, wash your hands, and keep pets off your pillow.

What the rosemary research actually says

The study everyone quotes is Panahi et al., published in SKINmed in 2015. Researchers split 100 men with pattern hair loss into two groups of 50. One group used rosemary oil, the other 2% minoxidil, for six months.

At 3 months: neither group showed a meaningful change in hair count.
At 6 months: both groups had more hair than at the start, with no significant difference between them.
Side effects: scalp itching rose in both groups but was more common with minoxidil.

It is genuinely interesting research, and it is why rosemary has become a staple of so many hair routines. It also has real limits, and we think you deserve to know them:

It is one small study, and it only included men.
It compared rosemary with 2% minoxidil, not the stronger 5% version many people use.
Results took six months of consistent, twice-daily use to show.
Rosemary oil is not a licensed medicine, and no cosmetic oil, ours included, is a treatment for hair loss.

Why rosemary is loved in hair care

Rosemary (Rosmarinus officinalis) is rich in antioxidant compounds such as carnosic acid and rosmarinic acid. It has a long history in scalp tonics, smells fresh and herbal, and pairs naturally with a scalp massage, which is a lovely ritual in its own right. If your hair loss is sudden, patchy or worrying you, see your GP or a dermatologist first: an oil supports healthy hair but can't diagnose or treat the cause.

Black Jamaican castor oil: the conditioner

Castor oil is pressed from the seeds of the Ricinus communis plant. Black Jamaican castor oil is made by roasting the seeds before pressing, which gives it its dark colour, nutty smell and slightly thinner feel than clear castor oil.

Around 85 to 90% of castor oil is ricinoleic acid, an unusual fatty acid that makes the oil thick and gives it its conditioning power. It coats each strand, helping to lock in moisture, smooth the cuticle and reduce the dryness that leads to breakage. Ricinoleic acid has also been studied for soothing, anti-inflammatory properties.

To be straight with you: despite its reputation online, there is no solid clinical evidence that castor oil makes hair grow, and dermatologists consistently say so. What it does well is condition. Hair that is less dry and less brittle snaps less, so you keep more of the length you grow. That is exactly why it is in the blend.

Pumpkin seed oil: the nourisher

Pumpkin seed oil is cold-pressed from the seeds of Cucurbita pepo. It is rich in fatty acids such as linoleic acid (omega-6) and oleic acid, along with vitamin E and plant sterols, which make it a light, nourishing oil for both hair and scalp.

It has also caught researchers' attention. In a 2014 placebo-controlled trial, 76 men with pattern hair loss took 400 mg of pumpkin seed oil capsules a day for 24 weeks. Hair counts rose about 40% in the pumpkin seed oil group compared with about 10% on placebo. Earlier animal studies suggest pumpkin seed oil may affect DHT, the hormone behind pattern hair loss.

The honest caveats: that study tested capsules taken by mouth, not oil on the scalp, and the capsules were a branded supplement. So we can't promise the same results from a hair oil. In Get to the Root, pumpkin seed oil is there to nourish the scalp and soften dry, dull strands.

Get to the Root: three oils, one ritual

Get to the Root is our daily hair and scalp oil, made to tackle dryness, dullness and brittle strands. Each oil plays a different role:

Ingredient	What it brings
Rosemary	Fresh, herbal scalp ritual, rich in antioxidants
Black Jamaican castor oil	Deep conditioning to lock in moisture and reduce breakage
Pumpkin seed oil	Lightweight nourishment for scalp and strands

It comes in two sizes: 30 ml for £20, or 50 ml for £35.

Shop Get to the Root

How to use it

Patch test first. Dab a little behind your ear or on your inner arm and wait 48 hours before using it on your scalp.
Part and apply. On dry or slightly damp hair, part it into sections and use the dropper to place a few drops directly along each parting.
Massage for 3 to 5 minutes. Use your fingertips, not nails, in small circles. It spreads the oil and feels wonderful.
Smooth the ends. Run any oil left on your hands through the mid-lengths and ends, where hair is driest.
Leave it on. Leave it on for at least an hour, or overnight with a silk scarf or an old pillowcase.
Wash out. Shampoo twice to lift the oil, then condition as usual.

Use it two or three times a week to start, and give it time. Hair grows roughly 1 cm a month, so judge your results over a few months, not a few washes. Avoid your eyes, and stop using it if your scalp becomes irritated.

Keeping your pets safe

Cats in particular groom off anything that lands on their fur, and their livers handle many compounds poorly. That applies to all topical products, not just minoxidil: rosemary essential oil, like most concentrated essential oils, is also best kept away from cats. A few simple habits keep everyone safe:

Apply hair oils and treatments in a room your pets can't get into.
Wash your hands well afterwards.
Let products absorb or wrap your hair before cuddling pets.
Keep pets off your pillow on oil nights, or use a pillowcase you can swap.
Store bottles closed and out of reach, and wipe up spills straight away.

If your pet has licked or touched any human skin or hair product and seems unwell, call your vet immediately.

FAQs

Can I use Get to the Root alongside minoxidil?
If you are using a medicine for hair loss, check with your GP or pharmacist before adding anything else to your scalp.

Is it suitable for all hair types?
Yes. Fine hair needs only a few drops at the roots. Thicker, curly and coily hair can take more through the lengths too.

Will it make my hair greasy?
It is meant as a pre-wash treatment, so it washes out. A thorough double shampoo removes it.

Can I use it during pregnancy?
Ask your midwife or GP before using products with essential oils while pregnant or breastfeeding.