Whisk together both flours, sugar, baking powder, and salt. Whisk together buttermilk, eggs, vanilla and oil. Whisk egg mixture into flour mixture.
Heat 1 tablespoon butter in a large non-stick skillet over medium heat. Working in batches and adding more butter as needed, pour 1/3 cup batter per pancake. Place 2-3 slices of nectarine on top of each pancake. Cook until small bubbles form on surfaces and undersides are golden brown. Flip and cook until browned on other side. Top with flaked coconut and maple syrup.