Elderflower Cordial This floral, sweet-smelling syrup is a perfect match with seltzer water or, better yet, champagne. I add lemon to my elderflower syrup to give it some zing, but the aroma is all elderflower.It is a delicate scent, very sweet and just a bit spicy. Incidentally, this is not the alcoholic elderflower liqueur. If you are looking for that, here is my recipe for elderlower liqueur, a St. Germain style drink.lderflower Cordial This floral, sweet-smelling syrup is a perfect match with seltzer water or, better yet, champagne. I add lemon to my elderflower syrup to give it some zing, but the aroma is all elderflower.