Position rack in top third of oven and preheat to 425°F. Line large baking sheet with parchment paper.
In a large bowl mix whole-wheat flour, all-purpose flour, baking powder, ginger and sugar.
Add butter pieces, mash into flour with fork and then using fingertips, rub in chilled butter until pieces are size of small peas.
Mix 1 cup buttermilk and lemon zest. Pour buttermilk mixture into dry ingredients and stir just until milk is blended in (it will be thick and somewhat sticky).
Add blueberries and gently fold in; not all blueberries will get fully mixed in.
Transfer dough to a floured work surface and divide dough in half. Form each half into a flat disc, then cut each disk into 6 wedges.
Transfer scones to prepared baking sheet, spacing 1 inch apart. Bake until scones are golden brown on top and toothpick inserted into center comes out clean, about 25 minutes.