This recipe is flexible; substitute raspberries or a blend of raspberries and blackberries if you prefer.
INGREDIENTS | MAKES ABOUT 6 PINTS
3 quarts blackberries
7½ cups granulated sugar
2 (3-ounce) pouches liquid pectin
Rinse fully ripe blackberries in cold water and drain.
Place berries into a stockpot.
Crush with a potato masher to extract juice. Stir in the sugar, mixing well.
Bring to a full rolling boil over high heat, stirring constantly.
Add pectin and return to a full rolling boil. Boil for 1 minute. Remove from heat.
Skim off foam. Ladle preserves into sterilized jars. Wipe rims. Cap and seal. Process in water bath canner for 5 minutes.