Preheat the oven to 375 degrees F. Line a 9″ x 9″ baking dish with parchment paper or use a non-stick spray to lightly grease the pan. Thoroughly rinse and dry the fresh blueberries, sorting through to remove any remaining stems and set aside.
In a large mixing bowl, combine the flour, oats, coconut oil, hemp hearts, sugar, salt and spices. Using your hands, gently work the ingredients together until the coconut oil is evenly distributed. Add the lemon zest. Using your hands again, mix thoroughly until all ingredients are well combined and a crumbly texture forms. Divide in half, spreading one half into the lined or greased baking dish. Press firmly into the bottom. Add a little more if needed to evenly cover the bottom of the baking dish.
Spread the fresh blueberries in an even layer on top of the crumb mixture. Add the remaining crumb mixture over the top, pressing lightly into the pan. Bake for 35-40 minutes, or until the topping becomes golden brown.
Remove from the oven and serve warm if you want a more crumbly texture. If you prefer bars, allow to cool completely before cutting into nine even squares. Serve with additional fresh berries, your favorite yogurt, or vanilla ice cream.