In a blender combine the cucumber slices, lime juice, simple syrup and salt. Blend until smooth.
Add the mint leaves and pulse until finely chopped. You want to avoid blending the mint leaves too much or you'll have a murky-looking popsicle.
Pour the mixture into popsicle molds and freeze for 30 minutes.
After 30 minutes, insert popsicle sticks into the molds and allow to freeze for an additional 7 1/2 hours (or overnight).
Unmold* and enjoy!
Simple Syrup Recipe:
1/2 cup sugar
1/2 cup water
In a small pot, combine the sugar and water. Stir to dissolve slightly. Bring to a boil over medium-high heat. Once the sugar has dissolved, remove from heat and allow to cool completely before use. *Some molds release the popsicleseasier than others. My foolproof way to get mine out is to running really hot water over the inverted popsicle mold, turn it right side up and unmold quickly. I run hot water over them again if they fail to release easily.