2 quarts fresh or frozen blueberries
4 cups water
12 cups white sugar
2 (3 ounce) pouches liquid fruit pectin
Place blueberries in a large kettle and crush slightly. Add water; bring to a boil. Reduce heat to medium; cook, uncovered, for 45 minutes. Strain through a jelly bag, reserving 6 cups juice. Pour juice into a large kettle; gradually stir in sugar until dissolved. Bring to a boil over high heat, stirring constantly. Add pectin; bring to a full rolling boil. Boil for 1 minute, stirring constantly. Remove from the heat. Skim foam. Pour hot into sterilized hot jars, leaving 1/4-in. headspace. Adjust caps. Process for 5 minutes in a boiling-water bath.