Place 3/4 c of strawberries & 3/4 c of blueberries with 1/2 c of raspberries in a blender. Blend at low speed for 30 seconds. Pour into a bowl & stir in the remaining blueberries & raspberries. Slice the remaining strawberries & use as a garnish. Serve immediately. If keeping, cover & keep for 3 to 5 days in the refrigerator, but it will not be as fresh tasting.