Cut the watermelon into manageable chunks, removing any seeds if necessary, and measure out 4 cups in a measuring cup or jug.
Place the watermelon chunks into the blender, add lime juice and a few mint leaves if using, then blend on high until completely smooth and vibrant red in color.
4 cups fresh watermelon chunks
Pour the blended watermelon mixture evenly into the ice pop molds, leaving a small gap at the top for expansion.
Insert sticks into each mold and place the molds in the freezer. Freeze for at least 4 hours or until completely solid.
To serve, remove the molds from the freezer and run briefly under warm water to loosen the pops. Gently pull out the watermelon pops to display their bright, juicy appearance.