Prepare the Blueberry Lavender Syrup:
In a saucepan, combine blueberries, sugar, and 1 cup of water.
Bring to a boil over medium heat, then reduce to a simmer and cook for about 5 minutes, or until the blueberries have burst and the mixture has thickened slightly.
Stir in the dried lavender buds and let it steep for about 5 minutes.
Strain the syrup through a fine mesh sieve into a pitcher, pressing down on the solids to extract as much liquid as possible.
Mix the Lemonade:
Add the freshly squeezed lemon juice to the blueberry lavender syrup.
Stir in 4 cups of cold water and mix well.
Taste and adjust the sweetness or tartness as desired by adding more sugar or lemon juice if needed.