In a small saucepan over medium heat, whisk together the water and sugar. Add the dried hibiscus and let it come to a simmer. Once it reaches a simmer, let it cook for 3 minutes, then use a slotted spoon to remove the hibiscus. Add the blueberries, then let cook for 5 minutes. Remove from heat and let cool completely.
Transfer the mixture over to a blender, then blend for 30-40 seconds until smooth. Strain and store in an airtight bottle or container in the refrigerator.