Does anything encourage hair growth?!

[MadameSapphire]

Going from short to long... (realise this may be a silly question!). Is there anything that can be used to encourage hair to grow? TIA.

Scalp massage.

Although my first thought was Cornucrescine. Horses hoof ointment, which is effective on scars to encourage hair regrowth. But it's brown and sticky, so...yeah, maybe not!