In a large pot, boil water. Once water is boiling, add glass canning jar and lid. Both jar and lid must be sterilized and hot before jam can be put in it. Leave jar in boiling water until ready to use.

In a small pan over medium heat, add strawberries and blueberries. Add sugar and lemon juice.

Mash berries with fork or potato masher until desired consistency.

Turn heat to high and bring jam mixture to a rolling boil. Mixing constantly., let mixture boil until thickened (about 10 minutes).

Remove canning jar from boiling water using tongs and put jam into jar. Cover tightly with lid. Let it cool completely before storing in refrigerator.

Since this jam has no preservatives, it will only last up to a week in the fridge. So... Eat up!