In a sturdy glass, add the diced peaches, peach juice, honey, and minced fresh rosemary. Gently muddle with the back of a spoon or muddler to release the peach juices and rosemary aroma.
Fill the glass with ice cubes.
Slowly pour ginger beer over the ice until the glass is nearly full.
Gently stir to combine. Garnish with a fresh rosemary sprig and, if desired.