It's Beltaine ritual, gathering these spring blossoms, for refreshing drinks for the coming summer, and to dry for healthful teas throughout the year.. just as the ancestors have, for thousands of years...
strain the flower mixture back into the pot, and bring to the boil again, then cool, and pour into warm (I put mine in the oven 20 minutes 160 degrees from cold) sterilized glass jars with pop top lids, or whatever you prefer whilst it is warm.
This recipe filled 5 passata jars, and assorted juice bottles I had saved & washed. I really can't tell you the exact yeild, but it is quite enough for me to share and enjoy with family and friends.
You're meant to refrigerate this, but mine is on stone benches in a cellar, as my fridge is tiny. This works well for me, and I wish you much joy if you ever make this cordial at Beltaine.
* In Australia, Elder is a garden shrub, not a wild plant, as in Europe - I planted a hedgerow garden, but that's another story!