Muddle the Blueberries and Mint: In a sturdy glass, add the fresh blueberries and mint leaves. Muddle them together to release the juices and flavors of the blueberries and the oils from the mint leaves.

Add Lime and Lavender Syrup: Squeeze the juice of one lime into the glass. Add the lavender syrup. Stir well to mix the flavors.

Mix in the Rum: Pour the rum into the glass over the muddled mixture. Stir well to combine all the ingredients.

Add Ice: Fill the glass with ice cubes to chill the mixture.

Top with Club Soda: Pour club soda over the ice to fill the glass. Gently stir to integrate all the components without disturbing the muddled mint and blueberries at the bottom.

Garnish and Serve: Garnish with a few whole blueberries, a slice of lime, and a sprig of fresh mint on top. Enjoy immediately!