Lower the oven rack to the lower third position and preheat the oven to 350.
Grease and flour a 9x5 inch loaf pan and line with parchment.
Sift together flour, baking powder, baking soda and salt. Set aside.
In a large bowl and using an electric hand mixer or stand mixer on high speed, beat the butter until smooth and creamy, about 1 minute. Add the sugar and beat on high spead until creamed, about 2 minutes.
With the mixer on low speed, add eggs one at a time, scraping down the sides of your bowl in between each addition.
In a small seperate bowl, whisk lemon zest, buttermilk and lemon juice.
Add the buttermilk mixture and dry ingredients to the butter mixture, alternating between wet and dry but ending in dry. Mix until combined. Do not overmix.
Toss washed and dried berrries with 1 tablespoon flour to coat. Fold into the batter.
Pour into your prepared baking pan. Bake in preheated oven for 60 minutes, or until cake is golden and tester comes out clean.
Transfer pan to wire rack and allow the loaf to cool for 15 minutes.
Remove loaf from pan and allow it to continue to cool on the rack.