Sep 4, 2013 16:29 Watermelon Waldorf Salad Watermelon Waldorf Salad national Watermelon Promotion Board Sept. 04, 2013 Comments Photo provided by National Watermelon Promotion Board -- For a cool treat on a hot day, try Watermelon Waldorf Salad.Watermelon Waldorf Salad Serves 2 to 3. Recipe is from National Watermelon Promotion Board. 2 cups cubed watermelon (about ½-inch cubes) ½ cup sliced celery ½ cup seedless red grape halves Dash of salt ¼ cup Greek yogurt 2 tbls. sliced almonds, toasted 1. Stir together watermelon, celery and grapes in bowl. 2. Just before serving, stir salt into yogurt for dressing. You may want to add a little water to lighten the thickness. Pour mixture over fruit and stir until coated. Sprinkle with almonds.