In a large pot, combine dried sorrel, 4 cups of water, cinnamon sticks, and cloves.
Bring to a boil and let it boil for 8–10 minutes. Remove from the heat.
Remove from the heat, cover, and steep for at least 1 hour or overnight for a stronger flavor.
Strain the liquid into a large pitcher. (You should get about 2 3/4 cups of concentrate.)
Stir in the remaining 4 cups of water, sugar, and bitters. Taste and adjust the sugar or water as needed until the sorrel is as sweet and strong as you like.
Chill in the fridge. Serve over ice.