Spoon the pink watermelon flesh into a high-powered jug blender (or spoon into a large bowl if you’re using a hand blender) and blitz until smooth. Pour into ice-lolly moulds, leaving a 2cm gap at the top, then freeze for four hours.
Blitz the kiwis, coconut yogurt and spinach in the blender until smooth (or in a bowl with a hand blender).
Remove the lollies from the freezer and top each one up with the puréed kiwi mix. Freeze for another four hours, or overnight.