Rosemary oil may help stimulate hair growth if applied to your scalp. But the process can take at least six months, and even then, the results can be mixed. Discover 7 amazing benefits of using rosemary oil for hair growth . Learn how it strengthens follicles, reduces thinning, and boosts scalp health naturally. Natural hair care is gaining popularity with rosemary and onion oils leading the trend. Rosemary oil stimulates scalp circulation for hair growth . Some research shows that rosemary oil may help stimulate hair growth and slow hair loss . Learn more here.