In a large sauce pan, combine the strawberries and rhubarb. Crush the mixture together (I use my potato masher), and then add in the lemon juice. Bring to a boil and then let simmer, stirring frequently, until the rhubarb breaks apart.

Prepare your canning supplies. Bring the temperature of the glass jars up by processing them in hot water for several minutes, and heat a few cups of water in a small saucepan for the lids.

Stir in the pectin until dissolved. Bring back to a boil, and then add in the sugar all at once. Boil hard for a minute longer.

Skim off any foam and ladle the hot jam into the hot jars, leaving 1/4″ headspace.

Place the lids and bands on top, screwing on the bands just until fingertip-tight. Place the full jars back into the boiling water and process 10 minutes.

Remove from the water and place the jars on a towel. Let the jars cool. The seals should suck down (you’ll hear a popping noise as they do). Makes 7-8 eight-ounce jars.