You can make such lemonade if you bring a bunch of lavender from a trip to the south.
Bring 3 cups plain water with sugar and hibiscus to a boil. Cook over low heat for 5 minutes, remove from heat, add lavender flowers, leave for 2 hours.
Strain, add lemon juice, sparkling water, sweeten with sugar syrup to taste, and serve over ice, garnishing with a sprig of lavender blossom if possible.