Bring 8 cups of water to a boil in a large saucepan over medium heat.

Add blackberries, coarsely chopped fresh mint leaves, and rosehip and hibiscus tea bags to the boiling water.

Remove from heat.

Let the mixture stand at room temperature for 1 hour to allow flavors to infuse.

Strain the mixture through a sieve into a pitcher, discarding the tea bags and solids.

Add granulated sugar and fresh lemon juice to the tea.

Stir until the sugar dissolves completely.

Pour the blackberry aqua fresca into glasses or cups.

Garnish each serving with a fresh mint sprig before serving.