Preheat an oven to 375 degrees F (190 degrees C). Lightly grease a baking sheet.
Whisk together the flour, baking powder, and salt in a mixing bowl. Cut the butter into the flour mixture with a knife or pastry blender until the mixture resembles coarse crumbs. Whisk together the egg, milk, agave nectar, lemon zest, lemon juice, and ginger in a separate bowl; stir into the flour mixture until moistened.
Turn the dough out onto a lightly floured surface and knead briefly, for five or six turns. Pat or roll the dough out into a 1/2-inch-thick round. Cut into 8 wedge-shaped pieces and place onto the prepared baking sheet.
Bake in the preheated oven until golden brown, about 20 minutes.
