This is the one you dilute with water. It keeps for ages in the fridge - I've still got a little of the last jar from last year, and it's as good as it was on day one. Some people put it into plastic bottles and freeze them, but my friend Vivien says that the nasties in the plastic leach into the liquid, so perhaps it's not such a good idea.
Whatever, this is simple to do, the sort of thing that makes you feel tremendously clever and together, when actually you haven't done very much at all. The effect has been slightly lessened by the sort you can buy in the supermarket, which really does taste like home-made, because it is home-made, but on a much much larger scale. But it's still worth doing, if only to save money (it's amazing what they charge for a bit of flavoured sugar water!).
I've been making it for years, using a recipe that's been in my manuscript recipe book for as long as I can remember, so it's in imperial measures, rather than metric. The exact quantities don't much matter, because all that sugar and the citric acid keep it all sweet (in both senses) for years.
But when you've made it, don't just limit yourself to diluting it with water to drink on a hot day ... you can use the syrup to flavour gooseberries (just coming in to season), or apricots (the first from Sicily are just appearing in the shops now), or to make a sorbet.
25 elderflowers, stalks removed
2 lemons, grated, squeezed, and cut up
50g citric acid
1 litre cold, previously boiled, water
Put all the ingredients into a bowl in a cool place for two days. Stir occasionally. Or not. Strain and bottle. Dilute to drink. Keep in the fridge.
If you're impatient (and who isn't?), there's an alternative way to do this:
Quick elderflower syrup
Stir 500g sugar into a litre of water, with the juice of two lemons. Boil for about a minute, then add 10 elderflower heads. Remove from the heat, cover the pan, and leave to cool. When it's completely cold, bottle and strain.
The only reason I don't use this recipe (although I have made it in the past) is because it's a little more of a palaver.
Just make sure that the flowers are completely white - any brown and the whole batch will taste filthy (Sarah Raven says it makes it taste like cat's pee ... I wouldn't know!).
Er zijn plekken in Hamburg waar ik niet eens wil lopen  - Zoals bijvoorbeeld... de Reeperbahn. Het moet even vinden alle reisgidsen. Nou... vink! En klaar met die troosteloze bende. Nu is dat ook helemaal niet ...
23 hours ago