Mrs Grieves, in The Modern Herbal of 1931, swears by elderflower leaves, bruised or 'in decoction' to drive away flies, midges and mosquitoes. Bruised leaves can be worn in a hat or rubbed on the face. Alternatively, make an infusion of the leaves and dab the mixture on afterwards with a cotton wool pad.
Gather some sprigs of fresh leaves from the Elder.
Remove the stems and place the leaves in a jug.
Pour on enough boiling water to cover the leaves.
Cover with a lid immediately.
Leave for a few hours, until the liquid infusion is cold.
Strain, decant into a bottle and keep tightly corked.
Tip: make fresh infusions often, as over time, it tends to lose its efficacy.