Blackberry Rhubarb Jam Recipe
This blackberry rhubarb jam recipe combines tart rhubarb with juicy blackberries for a jewel-toned jam that’s bold, bright, and perfectly sweet-tart. Whether you make it with pectin for a firm set or old-fashioned without, it’s a versatile jam that pairs beautifully with bread, cheese boards, or desserts.
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Servings: 6 8-oz jars
Calories: 80kcal
Cost: $9
Equipment
- 1 Large heavy pot Stainless steel or enamel
- 1 Wooden spoon For stirring
- 1 Potato masher For crushing blackberries
- 1 Canning funnel For clean jar filling
- 6 8-oz canning jars Sterilized with lids and bands
- 1 Water-bath canner Or large stock pot with rack
Ingredients
- 4 cups Rhubarb chopped About 1¼ pounds, fresh stalks only
- 3 cups Blackberries Rinsed and lightly mashed
- 3 cups Granulated sugar Adjust down to 2½ cups for less sweetness
- 2 tbsp Lemon juice Fresh-squeezed adds acidity and brightness
- 1 pkt Pectin optional 1.75 oz packet if making firm-set version
- ½ cup Honey optional Replace part of sugar for variation
Instructions
- Chop rhubarb into small pieces and mash blackberries lightly.
- Place rhubarb, blackberries, and lemon juice into a large heavy pot.
- With pectin: Stir in pectin, bring to a rolling boil, add sugar all at once, boil hard for 1–2 minutes, then remove from heat.
- Without pectin: Add sugar and cook over medium heat, stirring often, until jam thickens (30–40 minutes). Test by spooning jam on a chilled plate, if it wrinkles, it’s ready.
- Ladle hot jam into sterilized jars, leaving ¼ inch headspace.
- Wipe rims, seal, and process jars in a boiling water bath for 10 minutes.
- Let cool undisturbed for 3 hours. Store sealed jars in pantry for up to 1 year.
Notes
For a deeper flavor, replace 1 cup of sugar with ½ cup honey.
Add orange zest or vanilla for a flavor twist.
Jam too runny? Re-boil with 1 tbsp pectin mixed into ¼ cup sugar.
Delicious as a spread, glaze, or dessert topping.
Nutrition
Calories: 80kcal | Carbohydrates: 21g | Sugar: 19g | Calcium: 15mg