Elder flower cordial

We have not bought soft drink/soda or many years but during summer I like having a cold soft drink on hand to serve the family and for anyone who drops buy. We've had many glasses of lemon, orange and passionfruit cordial here, as well as homemade ginger beer, now I've added elder cordial to the list of cool drinks I can serve. We planted our elder bush last year and although it was in flower