Grease and flour the bread or loaf pan. Preheat oven to 350 F. Sift together flour, baking powder, and salt. In another bowl, cream butter with sugar until fluffy. Then add lemon rind, chopped flowers, and eggs, and beat mixture just until thoroughly combined. Stir in lemon juice. Gradually mix in dry ingredients and nuts, mixing until blended. Spoon into prepared pan and bake 50 to 55 minutes. Cool on rack.