I used the elderflowers yesterday afternoon to make cordial which will be ready after 2-3 days, more flavour is infused if left longer.
1.5 l of boiling water
1 kilo sugar
20 large elderflower heads
50g of citric acid (optional)
The elderflowers were put into the tub (I had about 30, but a few weren't large), and I added lemon zest and then sliced the lemons too and added them. To that was added a cooled syrup made from 1½ litres of boiling water and 1 kilo sugar. I also added 50g Citric acid as this helps to preserve it if keeping it for a while - not that I think it will last that long!
Can't wait for the weekend to bottle and try some.