Emma ThorntonRosemary oil has become one of the most talked-about natural hair treatments in recent years — and for good reason. A well-publicised 2015 clinical trial found that rosemary oil performed as well as minoxidil (the active ingredient in Rogaine) for stimulating hair regrowth in people with androgenetic alopecia, with fewer side effects. Since then, it’s become a staple in natural hair care routines worldwide.
But most people buy expensive pre-made rosemary oil when making your own is surprisingly simple, significantly cheaper, and lets you control the concentration and the carrier oil. Here’s exactly how to do it.
What You’ll Need
- Fresh or dried rosemary sprigs (fresh gives a more vibrant oil; dried lasts longer)
- A carrier oil — jojoba oil, fractionated coconut oil, or sweet almond oil are best for hair
- A clean, dry glass jar with a lid
- A small saucepan (for the quick method) or a sunny spot (for the slow method)
- A fine mesh strainer or cheesecloth
Method 1: Cold Infusion (Slow Method — Best Quality)
Time required: 2–6 weeks
- If using fresh rosemary, lay the sprigs on a clean towel for 24–48 hours to dry slightly — excess moisture causes mould in the oil
- Place the rosemary sprigs in a clean, dry glass jar and pack them in loosely
- Pour carrier oil over the rosemary until it’s completely submerged — no rosemary should be above the oil line
- Seal the jar tightly and place in a warm, sunny spot (a sunny windowsill is perfect)
- Shake or turn the jar gently every day
- After 2–6 weeks, strain the oil through cheesecloth or a fine strainer into a clean bottle
- Store in a dark, cool place and use within 6–12 months
Result: The highest quality rosemary oil — gentle extraction preserves delicate aromatic compounds and produces a fragrant, potent infusion.
Method 2: Heat Infusion (Quick Method — Ready in Hours)
Time required: 2–4 hours
- Place rosemary and carrier oil in a small saucepan
- Heat over the lowest possible flame — the oil should feel warm but never hot. You’re looking for a temperature of around 40–50°C (104–122°F)
- Maintain this very low heat for 2–4 hours, checking regularly. The oil should never bubble or smoke
- Remove from heat, allow to cool completely
- Strain through cheesecloth into a clean dark glass bottle
- Store in a cool, dark place and use within 3–6 months
Result: Faster and effective — good for those who want their oil sooner. Slightly less aromatic than the cold infusion method but still highly effective for hair use.
The Best Carrier Oils for Hair
| Carrier Oil | Best For | Notes |
|---|---|---|
| Jojoba oil | All hair types | Closest to scalp’s natural sebum; lightweight, non-greasy |
| Fractionated coconut oil | Fine to medium hair | Stays liquid; lightweight; absorbs easily |
| Sweet almond oil | Dry or damaged hair | Rich in vitamins E and D; nourishing |
| Castor oil | Thick or very dry hair | Very thick — mix with lighter oil (1:3 ratio) |
| Argan oil | Frizzy or coarse hair | Adds shine; good for hair surface |
How to Use Rosemary Oil for Hair Growth
- Frequency: Apply 2–3 times per week for best results
- Amount: A few drops (3–5) massaged into the scalp directly — you don’t need much
- Application: Part your hair in sections and apply directly to the scalp with a dropper or fingertips. Massage in circular motions for 2–4 minutes to improve blood circulation
- Leave in time: Leave for at least 30 minutes, or overnight for deeper treatment. Place a shower cap over your hair if leaving overnight to avoid staining pillows
- Wash out: Shampoo normally — you may need two rounds to fully remove the oil
- Timeline: The 2015 clinical trial showed significant hair growth results after 6 months of consistent use. Give it at least 3 months before evaluating results
Frequently Asked Questions
The simplest method: pack fresh or dried rosemary sprigs into a glass jar, cover completely with a carrier oil like jojoba or fractionated coconut oil, seal the jar, and leave in a warm sunny spot for 2–6 weeks. Strain out the rosemary and transfer to a dark glass bottle. For faster results, gently heat the rosemary and oil in a saucepan at very low temperature for 2–4 hours instead.
Yes — and often better. Commercial rosemary hair oils are frequently diluted or contain added preservatives and fragrance. Homemade rosemary oil lets you control the concentration and the quality of carrier oil used. The 2015 clinical trial used rosemary essential oil (highly concentrated, steam distilled), but infused rosemary oil made at home contains the same beneficial compounds in a gentler form.
Cold-infused rosemary oil stored in a dark glass bottle in a cool, dark location will last 6–12 months. Heat-infused oil has a slightly shorter shelf life of 3–6 months. Always check for any rancid or off smell before use — if it smells odd, discard it.
Yes, but let it dry for 24–48 hours first. Fresh rosemary contains moisture that can introduce water into the oil, promoting mould growth. Lay the sprigs on a clean cloth in a warm spot until they feel slightly wilted but not fully dried out, then proceed with your chosen method.
This article is for informational purposes only.
Related Articles
- How to Dilute Rosemary Oil for Hair: The Right Ratios Explained
- How Long to Leave Rosemary Oil in Hair for Best Results
- How to Make Rosemary Water for Hair Growth
- Does Mielle Rosemary Oil Cause Hair Loss? The Truth Behind the Reports
- Castor Oil for Hair Growth: Does It Actually Work?
Related reading: How to Dilute Rosemary Oil for Hair, How Long to Leave Rosemary Oil in Hair, How to Make Rosemary Water for Hair, Castor Oil for Hair Growth.
Emma Thornton
