Celery and Parsnip Soup with Green Onion Dill Matzo Balls

Name: Celery and Parsnip Soup with Green Onion-Dill Matzo Balls
Ingredients: 6 tablespoons (3/4 stick) unsalted pareve margarine; 9 cups thinly sliced celery stalks (about 2 bunches); 2 cups finely chopped peeled parsnips (about 12 ounces); 1 1/2 cups chopped green onions; 1 large garlic clove, chopped; 1 thin round of peeled fresh ginger; 6 cups (or more) homemade chicken stock or canned low-salt broth; 1/2 cup finely chopped celery leaves; Green Onion-Dill Matzo Balls