Hang 3 bunches of basil in a punch bowl. Cut the melon in half and scrape out the seeds. Remove the flesh with a baller or spoon and place in the punch bowl. Pour the Gewürztraminer over it and chill with the lid on for 1 hour.
Remove the basil bundle. Pluck the leaves from the fourth bunch and add to the punch bowl. Pour the well chilled sparkling wine.
You can also use melons of different colors, such as Charentais or honeydew melons.