Preheat an oven to 400°F/220°C and line a baking sheet with parchment paper.
Combine the flour, sugar, baking powder, soda, salt and zest to a mixer bowl.
Add the butter and rub it into the flour with your fingers until it resembles fine meal.
Stir in the buttermilk and blackberries and mix just until combined. See the “It’s that easy” tip.
Turn the scone batter onto a lightly floured surface and divide it into 2 mounds.
Sprinkle the top of each mound with a little flour and gently pat each into a circle about 6-inches in diameter. Cut each disk into 6 wedges.
Transfer the scones to a parchment lined baking sheet, brush with the 2 tbsp/30 ml buttermilk and bake them for 25 to 30 minutes or until they are golden brown and firm to the touch.
Cool on a rack.
Mix the powdered sugar and lemon juice together in a small bowl.
Drizzle the icing over the warm scones adding more lemon juice or water if it’s gloppy and not drizzly.
Serve warm or room temperature.