Bring 1/3 cup of water just to a boil in a small saucepan.
Add the jasmine tea, remove the pan from the heat, and steep for 4 to 5 minutes.
Strain into a clean pan, pressing to extract as much liquid as possible, and discard the tea leaves.
Add the sugar and lime zest to the pan. Over medium heat, stir until the sugar dissolves, then bring the liquid to a boil.
Reduce the heat and simmer the syrup for 1 to 2 minutes. Remove the pan from the heat and stir in the lime juice.
Place the kiwi, melon, and grapes in a serving bowl and pour on the syrup.
Cover and marinate in the refrigerator for 4 to 6 hours.
Remove from the refrigerator at least 20 minutes before serving, toss gently, and garnish with mint.