In a small saucepan, combine the water, sugar, and culinary dried lavender buds. Bring the mixture to a gentle simmer over medium heat, stirring constantly until the sugar has completely dissolved.
Remove the saucepan from the heat immediately, cover it, and let the lavender steep for 15-30 minutes. Steeping longer will result in a stronger lavender flavor.
Once steeped, strain the syrup through a fine-mesh sieve into a clean jar or bowl. Press gently on the lavender buds with the back of a spoon to extract all the flavorful liquid. Discard the spent lavender buds. Allow the lavender simple syrup to cool completely before proceeding.
In a large pitcher, combine the freshly squeezed lemon juice, the 3 cups of cold water, and all of the cooled lavender simple syrup. Stir everything together thoroughly until well mixed.
Taste your lemonade! If you prefer it tarter, add a little more lemon juice. If you like it sweeter, stir in a bit more simple syrup (you can quickly make more if needed, just scale down the recipe).
Fill glasses with ice, pour in your vibrant homemade lavender lemonade, and garnish each glass with a fresh sprig of lavender and a thin slice of lemon.