For creamy strawberry: Place strawberries, sugar and salt in a mixing bowl and toss together. Allow mixture to sit for 10 minutes. Pour mixture into a blender with the remaining ingredients and puree until smooth. Pour mixture into an airtight container and place plastic wrap directly over the puree. Place in refrigerator and chill for 3 to 6 hours.
For creamy blueberry: Place blueberries, sugar and salt in a mixing bowl and lightly mash. Toss together. Allow mixture to sit for 10 minutes. Pour mixture into a blender with the remaining ingredients and puree until smooth. Strain mixture into an airtight container and place plastic wrap directly over the puree. Place in refrigerator and chill for 3 to 6 hours.
For creamy lemon: Place all ingredients into a blender and puree until smooth. Pour mixture into an airtight container and place plastic wrap directly over the puree. Place in refrigerator and chill for 3 to 6 hours.
To assemble: Fill one third of each popsicle mold with the strawberry puree. Place mold into freezer and allow to freeze completely, 1 to 2 hours. Continue to fill molds another third of the way with the lemon puree. Place mold back into the freezer and allow mixture to semi-freeze, about 30 minutes. Once second layer is slushy, but not fully frozen, carefully push popsicle sticks into center of each mold. Place back into freezer and allow to freeze completely, 1 to 2 hours. Fill molds the remaining third of the way with the blueberry puree and freeze for about 3 hours.
To serve: Dip molds in warm to hot water for about 10 seconds to help loosen from molds. Serve immediately as popsicles melt quickly.