To make the elderflower syrup, pick about 20-25 blossom heads. Make sure the blossoms have fully bloomed.
Gently shake the heads back and forth for a while to remove bugs. You will also see some pollen disappear when you do so.
Then cut the flowers off the stems. This means you need less water and the syrup ends up being more concentrated.
Cut the lemon into pieces.
Now put the florets in a pan and put just under water. Add the lemon pieces. You can use a saucer to weigh it down slightly. Let this soak for 24 hours.
The next day, first pour the blossom with water through a sieve. You collect the liquid, of course. Discard the blossom and the pieces of lemon.
You repeat this one more time but this time through a cheesecloth or clean tea towel so that all the leftovers from the plant are left behind. The syrup will be cloudy. This is fine and is due to the pollen.
Now put the liquid back in the pan and add about 750 g of sugar to 1 litre of water. That is a huge amount, but remember it is a syrup so you drink it diluted with water.
Now heat the syrup gently and let the sugar dissolve. It doesn't need to boil any further. So when the sugar has dissolved, your syrup is ready. Store in clean bottles in the fridge.
Notes
Nutritional value for the entire recipe. Remember you use a small amount of the liquid when preparing drinks and such.