Shake out the flower umbels well, because in the fine flowers are often small flies.
Put the flower umbels in a suitable bowl, pour the boiling water, add sugar and citric acid, stir well.
Leave at room temperature for 24-two days. Stir from time to time so that the sugar and citric acid dissolve well.
Now filter the syrup through a sieve or crockery, bring to the boil, pour into small, well-cleaned, pre-warmed bottles to the brim on the spot and seal, keep cooled and dark.