Preheat the oven to 425°F and prepare your baking sheet with parchment paper or a silicone mat.
In a mixing bowl place the flour, sugar, lavender, baking powder, and salt and stir to combine.
Grate the cold butter and add it to the flour mixture. Use a pastry cutter to create a crumbly mixture, just enough to combine everything but don't overmix or your scones will be dense.
In another mixing bowl, add the sourdough discard and heavy cream and stir together. Add the discard mixture to the flour mixture, and stir just until the dough comes together.
Pour the dough onto a lightly floured surface (not too much flour or your scones will be dry) and knead a few times until everything comes together into a ball. The dough will be just slightly sticky. Gently pat the dough into a circle about 8" in diameter and about 1" thick.
Cut the circle into 8 wedges. Place the scones on your prepared baking sheet. Brush the top of the scones with heavy cream, and sprinkle with coarse sugar and more lavender buds if desired.
Place the scones into the oven and bake for 16-20 minutes until the tops and edges are just starting to brown. Allow the scones to cool on the pan for a few minutes after baking.
While the scones are baking or cooling, make the lemon glaze by combining the lemon juice, powdered sugar, and zest in a small bowl. Whisk together and drizzle on top of the warm scones. You can always add more juice or powdered sugar for your desired sweetness and consistency.