Rinse the elderberry flowers - They must be just
in bloom. Cut the lemon into thin slices and mix with the flowers
and the remaining ingredients in a reasonably large container: stir.
Cover the container and leave in a warm place.
The elderflower juice can be drunk after 24 hours. If necessary,
add honey and lemon to taste.
After 2-3 days the drink will begin to effervesce.
Then sieve, put into screw top bottles and store in a dark room.
The juice will turn into sparkling wine in about 4 weeks.