Mix lemon juice, water, and starter together.
Add lemon zest in with flour and sugar.
Let it bulk ferment overnight.
Fold in blueberries while forming the loaf.
Refrigerate for 6 hours after forming before baking.
Bake at 450°F in a Dutch oven for 30 minutes with the lid on, then 15 minutes with the lid off.
Let cool for about 2 hours before cutting.