Strip the peels from the oranges and lemons using a vegetable peeler. Try to remove just the peel, leaving behind as much of the bitter white pith as possible. Roughly chop the sage leaves. Make sure the bay leaves, peppercorns, and garlic cloves, and rosemary are measured out and ready to go.
3 oranges, 3 lemons, 1/2 cup sage leaves, 2 bay leaves, 1 tbsp peppercorns, 5 cloves garlic, 2 sprigs rosemary
Bring 1 quart (4 cups) of the water to a boil in a large saucepan or stock pot on the stovetop.
4 quarts water
Once boiling, add the salt and stir until dissolved.
1 cup kosher salt
Add the orange and lemon peels, chopped sage, bay leaves, peppercorns, rosemary, and garlic. Let the water return to a boil, then remove from heat.
Let the brine concentrate cool until no longer steaming, then stir in the remaining 3 quarts of water. Check the temperature of the brine; it should be room temperature or lukewarm.
Add 4 cups of ice to the solution to cool it even further.
Remove the poultry from its package and pat dry. Remove the giblets and save for making gravy. Place the poultry in a large pot, brining bag, or other container large enough to keep it submerged. Pour the brine over the poultry. Make sure the poultry is submerged, though it's ok if the boney tips of the legs stick out the top. If needed for larger turkeys, prepare additional brine solution (1/4 cup of salt dissolved in 4 cups of warm water) in order to cover the turkey. If the poultry is floating, weight it down with a plate or other heavy object.
Brine for 12 to 24 hours. Cover the poultry and keep refrigerated during the brining process.