In a large stainless-steel saucepan set over medium-high heat, combine rhubarb with sugar, water, cloves and ginger. Gently bring to a boil, then reduce to a simmer until rhubarb is soft, about 5 minutes.
Strain through a sieve and wait until comes to room temperature before serving. Chill in fridge or serve over ice. Garnish with fresh mint.