Wash and dry the rhubarb and cut it into 2 cm slices.
Place in a pot with 2-3 cups of water. Bring to a boil and simmer for 5 minutes until rhubarb is tender.
Strain rhubarb, including water, through a fine sieve into a pot.
Place the pot on the stovetop and add sugar; bring everything to a boil once. Reduce heat and boil down slowly until you have a syrup. (about 30 Minutes)
Fill the hot syrup into a bottle.
Pour the syrup into a glass,
fill up with water,
Add crushed ice, a few drops of lemon juice, and rose water.
Decorate with mint leaves.