Rinse the blueberries thoroughly. Bring the blueberries and 800 ml (approximately 27 ounces) to a boil in a saucepan. Add the cinnamon and cloves, and simmer the mixture for 15 minutes. Remove from the heat, let cool, then pass the mixture through a fine strainer lined with cheesecloth. Squeeze the berries well to extract all of the juice. Place the juice back into the saucepan. Mix in the sugar, lemon juice, and orange juice and stir until combined. Simmer the mixture until syrupy, stirring occasionally. This should take about 30 minutes, and you should have about 1 liter (approximately 1 quart) of the syrup.
Pour the syrup into prepared bottles, seal tightly, and cool completely.