1 1/2 qts. stemmed blueberries, crushed
1/4 c. lemon juice
1 cinnamon stick
7 c. sugar
2 (3 oz.) pkgs. liquid fruit pectin

Combine all ingredients except fruit pectin in a Dutch oven; bring mixture to a boil, stirring occasionally until sugar dissolves.

Cook at a rolling boil 2 minutes, stirring frequently; remove from heat. Discard cinnamon stick. Add pectin to blueberry mixture and stir 5 minutes. Skim off foam with a metal spoon.

Quickly pour jam into hot sterilized jars, leaving 1/8" headspace; cover at once with metal lids and screw metal bands tight. Process 5 minutes in boiling water.