
Chamomile cordial is a sweetened, acidified chamomile infusion — apple and hay, soft and quiet. The acid is what separates a cordial from a plain syrup, and the ingredients list says whether a given bottle has it.
Strong chamomile tea sweetened with honey is the practical home version and the closest match. Elderflower cordial keeps the floral register and trades the hay note for something rounder.
Chamomile tea
The unsweetened infusion — the same aroma with none of the sugar, so the drink takes its sweetness from elsewhere.
Elderflower cordial
The floral syrup that a bar actually keeps. Honeyed and fuller where chamomile is drier and hay-scented, so a drink built on it comes out sweeter and needs its lemon kept up.
Refrigerate once opened and use it inside a month. Chamomile is a delicate infusion and it goes flat rather than off: the honeyed, apple-like note thins out first, leaving sweetness behind. Homemade keeps about two weeks cold.