Found on sugarcrafter
* 3-1/2 cups chopped fresh or frozen rhubarb
* 1/2 cup water
* 2-1/4 cups coarsely chopped fresh or frozen blueberries
* 1 Tbsp lemon juice
* 1 package (1.75 oz) powdered pectin
* 5-1/2 cups sugar
Place the rhubarb in a large pot with the water. Bring to a boil over high heat. Cover and reduce the heat to low and simmer for about 5 minutes.
Add in the blueberries, lemon juice, and pectin, and mix well. Bring to a boil over high heat, stirring constantly. Add in the sugar, then return to a full boil and boil hard for one minute, stirring constantly.
When ready to can, prepare your supplies. Bring the temperature of the glass jars up by processing them in hot water for several minutes. Heat a few cups of water in a small saucepan for the lids.
Remove the rhubarb mixture from heat. You can pour it into the jars now, or process in your food processor like I did if you want the mixture to be a little smoother. When the jars are ready, fill them with the jam to 1/4″ headspace and place the lids and bands on top, screwing on the bands just to fingertip-tight. Place the full jars back into the boiling water and boil 10 minutes. Remove from the water and place the jars on a towel, and let the jars cool. The seals should suck down (you’ll hear a popping noise as they do). Makes 6 eight-ounce jars.