Since you have already attained the age of 19 and your height as indicated by you is not that much bad. However you may try the following tips for the growth of your height-
1) You need to take proper rest in night. A sound sleep stretching for eight hours is essential.in that way, there would be production of Human Growth Hormone responsible for growth in height.
2) Enough protein and Calcium are essential for the healthy growth. Hence ensure that your diet should comprise enough Curd, Eggs, Chicken and Cheese apart from regular intake of milk.
3) As far as possible avoid unnecessary stress and in order to combat stress you may take four to five leaves of Tulasi early in the morning.
4) Engage in muscle -stretching exercise regularly for at least an hour regularly such as Car- stretch, Cobra - stretch, Bow- down several times and Twisting etc. Such exercises would help you in the growth of height. Cycling and Jogging would also be helpful.
5) Two tea- spoon of Aswgandha of any Ayrvedic - Pharmactuals may be added in the warm milk and its regular use for 45 days would help you in height - growth.