Add water and sugar to a small saucepan. Bring to a gentle simmer over medium heat, stirring until the sugar dissolves.
Turn off the heat. Add rosemary sprigs. Cover and let steep 15–20 minutes for a fragrant, not overpowering, infusion.
Strain out the rosemary. Cool completely. Store in a sealed jar in the fridge.
Fill a shaker (or a lidded jar) with ice.
Add cherry juice, lemon juice, and rosemary simple syrup. Start with 0.75 ounce syrup; you can add more after tasting.
Shake hard for 10–12 seconds until the outside feels icy.
Fill a rocks or highball glass with fresh ice. Strain the mixture over the ice.
Top with chilled sparkling water. Start with 2 ounces, then add more if you prefer a lighter, bubblier drink.
Garnish with a rosemary sprig and a cherry or lemon wheel. Lightly smack the rosemary between your palms to release aroma before adding it.
Too tart? Stir in a splash more rosemary syrup.
Too sweet? Add a squeeze more lemon or an extra splash of sparkling water.
Not enough rosemary? Give the garnish a gentle twist in the drink, or steep your next batch of syrup a few minutes longer.
