Preheat oven to 400°. Line a baking sheet with parchment paper.

For biscuits: In a large bowl, stir together flour, brown sugar, and zest. Using two forks or a pastry blender, cut in cold butter until mixture is crumbly. Stir in blueberries, sour cream, and buttermilk until dough comes together. Drop dough 2 inches apart on prepared pan. Sprinkle with turbinado sugar.

Bake until golden brown, about 15 minutes.

For glaze: In a small bowl, whisk together confectioners’ sugar and lemon juice until smooth. Drizzle glaze over warm biscuits.