Preheat oven to 375 degrees. Cream butter and 1-1/4 cups sugar until light. Add the eggs one at a time, beating well after each.
Sift together the flour, salt, and baking powder. Add dry mixture to the creamed mixture, alternately with the milk. Crush 1/2 cup blueberries with a fork and mix into batter. Fold in remaining whole berries and add oragne peel.
Fill large muffin cups (use paper liners or grease cups). Sprinkle tops with 3 teaspoons of sugar. Bake at 375 degrees for 20 to 30 minutes. Cool for 30 minutes before removing.