Square Root's Elderflower Soda is a limited seasonal release tied to the elder flowering season. The elderflower comes from Hackney Marshes, hand-picked by the Square Root team alongside local urban forager John the Poacher. That specificity of sourcing gives the soda a more freshly foraged character than the category average. It's almost water-white in the glass, with a soft, natural fragrance on the nose: elderflower blossom, light honey, and a faint grassy note. On the palate, the floral character leads gently, with a citrus edge that keeps the sweetness in check. The carbonation is fine and gentle, lifting the aromatics without overwhelming them. It drinks like a well-made elderflower cordial topped with sparkling water, but drier and more refined. When it's gone, it's gone until next year.