i really would advice that you get your hands on same rosemary oil, i sware by this stuff. make a misture of jojoba and coconut oil add drops of rosemary to it. use this to message your scalp. it feels amazing and smells great.
chin length you say? your hair has really grown in the last year n a half!

my hair: 3b, high porosity, high density and coarse hair (i think i finally figured that all out)
my hair loves conditioner only styling!
Oils and my own procuts are my hairs best friend
my hair goal length is bra strap length when curly.