Instructions

1. Put the sugar into a pan and pour over the boiling water. Stir until the sugar has completely dissolved (or heat the water and sugar up to boiling point). Let it cool to luke-warm.
2. Meanwhile peel the zest of the lemons in wide strips, then slice the lemons. Add these to the cooling water.
3. Stir in the citric acid to the cooled water.
4. Shake the elderflowers to remove any little insects, then place them in a large ceramic or glass bowl.
5. Pour over the liquid and stir well. Cover the bowl and leave it in a coolish place for minimum 24 hours ( or up to 48), stirring occasionally.
6. Strain through a sieve lined with muslin and pour it into sterilized bottles.
7. Store chilled.