Combine moscato and juices in a large pitcher and chill in the refrigerator for at least two hours.
To serve, add a thin layer of light corn syrup to a shallow dish, then add a thin layer of sugar to another shallow dish. Dip the rim of each glass into the corn syrup, and then into the sugar to coat.
I a small bowl, add ¼ cup of sugar. Rinse the cranberries and grapes and shake off the water
just slightly. Toss them into the sugar to coat. Slice the plums. Add one plum slice, one cranberry, and one grape to individual cocktail picks and add them to each glass as a garnish.