How long will my hair get?

im 15 years old in grade 9. My hair is about 4 inches past my shoulders. my hair in the picture. When I graduate & for prom I want to have reallly long nice hair with curls from a curling iron & sparkles. how long do you think my hair will grow from now till then ? and also from now to next september.

Hair grows 1/2 an inch to an inch every 1-2 months

Supposedly if you get it trimmed a bit on the full moon it will grow quicker, if you get it trimmed every now & then your hair will start growing quicker anyways, & eat horse-tail(it's a herb you can probably find at a new age shop, herbal shop, or something lile that) It helps make it thinker & keeps it from falling out, so when it gets really long it wont be too thin, & it also helps make your hair grow. Oh, another thing, your hair is made up of dead skin cells, so try excersizing more than usual for awhile, be really active. The more dead cells, the more it grows(so rumor has it). I know my hair grew practicly 6-8 inchies this school year alone. However, eery one is different. Best of luck to ya. 1_~