- 4 cups blackberries
- 3 cups sugar, or more to taste
- 2 cups raspberries
- 1 tablespoon lemon juice, or to taste
- Place a small plate in the freezer.
- Combine blackberries, sugar, raspberries, and lemon juice together in a heavy pot over medium heat. Stir, crushing some of the berries, until sugar is completely dissolved and mixture is heated throughout. Taste and adjust sugar and lemon juice as needed.
- Increase heat to medium-high and bring to a boil, skimming any foam that rises to the top. Boil for ten minutes. Remove plate from freezer and drop a teaspoon of jam on the plate. Return to freezer for 1 minute; if jam has set, the jam is ready for canning. If jam is still runny, return plate to freezer and continue boiling for another 5 minutes, then test again. Repeat this process until jam sets.
- Transfer jam to hot sterile jars, leaving 1/4 to 1/2 inch headspace, place lid on top and secure with ring. Process in a boiling water bath for 10 minutes.
If you prefer a smoother texture to your jam, puree the mixture with an immersion blender before boiling. Swirl some of this jam into Greek yogurt with a bit of grated lemon zest for a delicious breakast or dessert.
What others are saying
Jen the Mighty says:
Jam is so easy and so worth it to make yourself. Best of all, blackberries and raspberries are full of natural pectin so you don't need to add any extra! The lemon juice gives this a little extra tang.
Aja A says:
Very easy jam to put together. I love to make sausage-biscuit sandwiches and spread this on them. Also I like to make breakfast sausage and cheese balls and mix this jam with plain yogurt to dip them in. So delish!
Caro Hodgin says:
A lovely, ultra-simple, reliable jam recipe. I love making jam, and this recipe passed my discriminating test with flying colors! I love giving jam away for Christmas gifts, so made a batch of this jam now while berries are in season to give away several months from now.