Combine 2 cups of chopped strawberries and 1 cup of chopped rhubarb in a saucepan. Add 1 cup of sugar and 1 cup of water. Heat over medium until simmering, about 5 minutes.

Cook the mixture for 15-20 minutes until the rhubarb is tender and the mixture thickens into syrup.

Strain the syrup through a fine-mesh strainer into a bowl or jar, pressing down to extract syrup. Cool to room temperature.

In a tall glass, combine 4 ounces of syrup, 4 ounces of lime juice, and 4 ounces of gin or vodka if desired. Stir gently.

Pour in 12 ounces of sparkling water, stirring gently to combine while preserving carbonation.

Garnish with rhubarb ribbon, lime wheel, or fresh strawberry before serving.