Blueberry Rhubarb Jam

In a large saucepan, combine blueberries, rhubarb, sugar substitute, lemon juice, and cold water. Bring mixture to a boil, stirring often. Lower heat and simmer for 10 minutes, stirring often.

In a small bowl, combine boiling water and dry fruit pectin, using a wire whisk to blend well. Stir into blueberry mixture. Bring mixture to a boil again and continue boiling for 1 minute, stirring constantly. Remove from heat and continue stirring often for 1 minute.

Carefully ladle hot mixture into hot sterilized half-pint jars, leaving a 1/2-inch headspace. Seal and process in a boiling-water canner for 10 minutes.