Preheat oven to 400°F.

Coat an 8×8” baking dish with cooking spray.
In a large bowl, toss berries with whole wheat flour, sugar and zest.
Transfer the berry mixture to the baking dish and set aside.

In a medium bowl whisk together the whole-wheat flour, all-purpose
flour, 2 tablespoons sugar, baking powder, baking soda and salt. Cut in
the butter using 2 knives or a pastry cutter until many small pebble-sized pieces are formed.

In a small bowl or pitcher, whisk together buttermilk and oil. Add
buttermilk-oil mixture to the dry ingredients and mix until just moistened. Do not over mix.

Drop batter onto the fruit forming 6 mounds. Sprinkle with the remaining
teaspoon of sugar.

Bake 30 minutes, until fruit is bubbly and top is golden. Let stand at least 10 minutes before serving.