Does anyone know how old Brian was when he started growing his hair long?

Brian was 22years old when he grew his hair long. in the 年 1970. but he straightened his hair.
he was with 皇后乐队 [freddie mercury , brian may , roger taylor, mike gross]but john deacon wasn't in 皇后乐队 then

I THINK he was in his 30s when he started growing his long hair Pat Bowes louisville Kentucky