Place the peeled chopped cucumber and finely grated ginger in a wide bowl and mash firmly using a muddler or sturdy spoon until the cucumber releases a generous amount of juice and the mixture becomes highly aromatic. Let the mixture stand undisturbed for 5–7 minutes so the ginger can gently infuse its clean heat into the cucumber liquid. This short resting phase builds real depth and prevents the drink from tasting watery or one-dimensional.

Transfer the cucumber–ginger mixture into a fine-mesh sieve set over a large pitcher and press lightly with the back of a spoon to extract as much liquid as possible without forcing pulp through. The goal is a clear, pale green infusion with fresh vegetal aroma rather than a cloudy purée. Discard the solids once most of the liquid has been collected.

Add the elderflower syrup, fresh lime juice, mild honey, and a small pinch of fine sea salt to the pitcher with the cucumber infusion. Stir slowly until everything is fully dissolved and integrated. Taste the mixture carefully and adjust only in small increments. The base should feel slightly intense, floral, and bright at this stage because the carbonation and ice will soften the overall flavor later.

Add a generous amount of ice to the pitcher and pour in the well-chilled club soda as the final component. Stir gently once or twice only to combine while preserving carbonation. Over-stirring will flatten the drink and dull the delicate botanical notes.

Pour the finished spritz into ice-filled glasses and garnish with long cucumber ribbons and optional edible elderflower blossoms. Serve immediately while the drink is fully cold, aromatic, and sparkling.