Madriver,
we are talking about 2 different wines here.
First Elderberry wine which can be made around August-September over here when the berries are ripe.
They do not need any addition of flowers. I sometime mix them with blackberries and that even gives a better wine.
A heavy dark port style wine.
The other wine I was talking about is elderflower wine.
That is a white wine made from the petals of the elder, and sometimes from the complete screens.
It produces a fenomenal taste just like lychees.
I make loads of syrup from the flowers each year. Great for making icecream, or topping up icecream, or just as a nice beverage.
You can even make wine from the syrup. The recipes are here:
http://wijnmaker.blogspot.com/2008/02/vlierbloesemwijn-elderflower-wine.html
Last year I made about 3 gallon of this wine (10 liter).
Then I made 3 gallon from the fresh flowers and that was one of my best whites.
This year I am aiming at making 90 liter of fresh flowers instead of the syrup.
As eldferflowers are budding over here I will give you next week a really easy harvesting method on my web-log
Luc