Blueberry rhubarb jam is a less common combination, but is no less delicious than the more familiar strawberry version. It’s a perfect jam to make during the transition from spring to summer.
It’s jam month in the Mastery Challenge universe and so on Monday night, I hopped onto Facebook for some live jam making. I made a small batch of Blueberry Rhubarb Jam in for the folks who tuned in (you can watch it whenever you have time right here), chatted about my summer preserving plans (I’m going for mellow this year), and gave everyone a good look at my rapidly growing belly (yes, there are indeed twins in there).
What I particularly like about this fruit combination (fondly called Blubarb by some folks), is that the berries and rhubarb really balance each other, but it’s not as common as the strawberry rhubarb combo. When used in equal portions, I find that the blueberries bring body and sweetness to the jam, while the rhubarb offers up its signature tang and zip. The end result is something that is satisfying and wonderfully spreadable (I used some commercial pectin, but the blueberries contribute a goodly amount of pectin as well).
It might seem impossible, but this is the first time I’ve posted a recipe for this exact combination. I went simple with this batch, but next time I make it, I might add a bunch of lemon zest. Or perhaps some freshly grated ginger. I also believe that cinnamon and blueberries always go nicely together. There are so many different ways to take a basic recipe and transform it into something fresh and new-to-you. I think that’s one of the things I love most about canning. There are always so many themes open for riffing and exploration.
And if this particular jam doesn’t speak to you, make sure to explore some of the blueberry recipes from the archives.
- Basic blueberry jam
- Small batch blueberry cara cara orange jam
- Small batch spiced blueberry jam
- Cranberry blueberry jam (a good way to clean out the freezer)
- Wild blueberry jam
- Small batch blueberry ginger jam
- Blueberry cinnamon freezer jam
Blueberry Rhubarb Jam
Ingredients
- 1 pound blueberries rinsed and picked over for stems
- 1 pound rhubarb cleaned and diced
- 1 pound granulated sugar
- 2 tablespoons powdered fruit pectin
Instructions
- Prepare a small water bath canning pot and four half pint jars.
- Pour the blueberries into a non-reactive pot (I used a five quart Dutch oven for this batch and it worked nicely). Using a potato masher, work the blueberries until they're mostly crushed. Add the rhubarb. Whisk the pectin into the sugar and add that to the pot as well.
- Place the pan on the stove over high heat and bring the fruit to a boil. Cook, stirring regularly for 18 to 22 minutes, until the fruit starts to thicken into jam.
- Once the jam has thickened satisfyingly and has reduced by at least one-third, it is done.
- Funnel the jam into the prepared jars. Wipe the rims, apply the lids and rings, and process in a boiling water bath canner for 10 minutes.
- When the time is up, remove the jars and set them on a folded kitchen towel to cool. When the jars have cooled enough that you can comfortably handle them, check the seals. Sealed jars can be stored at room temperature for up to a year. Any unsealed jars should be refrigerated and used promptly.
I was thinking you could call this Blu-barb Jam?
What kind (brand) of pectin did you use here?
I used classic fruit pectin.
Don’t you mean Bluebarb jam?
I’m so excited for this recipe! I’ve been looking for a good recipe for bluebarb jam since there was a comment about it last year!
Last summer, we had a bumper crop of rhubarb (easily 10+ lbs out of the patch once a month, all summer!). I made strawberry rhubarb, raspberry rhubarb, blueberry rhubarb… but I have to say that my absolute favourite was the black cherry rhubarb. OMG it was so good! I want to try pineapple rhubarb next!
Can I use frozen blueberries? I found two bags deep down in the freezer.
I’ve not tried this recipe with frozen blueberries, so I can’t guarantee how it will turn out. You can certainly try it, though.
I will give it a try. I might add a half of a granny smith apple shredded to boost the pectin, if the blueberries are too juicy.
RE: the question whether frozen blueberries will work, YES I have used frozen and it was wonderful. Also I didn’t bother with pectin and it was fine.
Also wonderful: ginger. Add fresh ginger and a bit of cardamom.
So glad to hear it!
Thank you for this wonderful recipe, Marisa! I have blueberries in the fridge – getting ready to freeze them whole – but I also have a huge patch of rhubarb! Now I can make more jam. I’m going to try your recipe the nearest time. Thank you for sharing this!
Enjoy!
Can I double the recipe?
The cooking time will increase, but you should be able to do it.
Can I use frozen rhubarb as well as frozen blueberries?
Yes.
This is a great idea! I go blueberry picking with my best friend every year, and we look for new ideas to cook and bake with them. This is perfect. Thanks for your clear instructions and inspiring photos!
Thank you for a great recipe!. I doubled it. And it turned out amazing!
Can I use Pomona Fruit Pectin? I am vegan.
To the best of my knowledge, regular fruit pectin is vegan. This recipe has too much sugar for Pomona’s.
I would like to use Pomona’s since I have a lot of it. Can I use Pomona’s if I reduce the amount of sugar? Is that all I have to do?
A whole pound of sugar. Seems like a lot🤔
I guess a pound is only 2 cups…. sorry about that
Does this recipe need additional acid or are the blueberries/rhubarb enough to make it safe to store?
This recipe doesn’t need additional acidity for safety. Both blueberries and rhubarb have an average pH of between 3.1 and 3.4, well below the 4.6 cut off for safety.
Can you use frozen Rhubarb? Thanks!
Yes!
This is a very interesting recipe. Sounds fantastic. I think i will try it!! Thank you!!
It’s delicious! I hope you try it!
I really enjoyed this video. I have rubarb made strawberry rhubarb jam last year. Will definitely try this.
Last summer I made this recipe but with haskaps (also called honeyberries) instead of blueberries. So good and love the small batch size. Looking forward to making more shortly!
That sounds like a delicious swap!
It’s the end of blueberry season and I have chopped rhubarb in the freezer waiting for their Final Purpose. Yay!
If I were to add grated ginger (in the freezer, right next to the rhubarb), how much should I add? Is 1 Tablespoon enough? 2?
I feel like 1 tablespoon should be enough. But add some and taste. You can always add more, but you can’t take any away.
Thank you. Can this be doubled and then processed in pint jars?
Yes. Just know that the cooking time will increase some. The processing time is the same for pint jars.
Can you make this without pectin?
It is safe to do so, but the jam will be runny.
Can I use liquid pectin instead of powder
I find that liquid pectin isn’t as effective as powdered. So the set may not be as firm. But there’s no reason not to try it if that’s what you have.
My favorite fruit is blueberry and second is rhubarb. This recipe is easy to follow. I found that the sugar was a little too much for me as I was looking for the tartness that both fruits can offer.
My family, who are not big blueberry fans, prefer this jam to strawberry rhubarb. Again the tartness won them over.
Boiling the jam to the correct thickness before processing made the whole process even better as there is no gamble upon opening as to whether it set it not.
I’m so glad to hear that the recipe worked well for you.
Great base recipe! We modified it to our tastes adding 1/4 cup of lemon juice and using liquid pectin (following liquid pectin instructions) instead of powdered and it’s perfect! Thanks!
I’m so glad to hear it!
Can the sugar be cut down safely?
Read this. https://foodinjars.com/blog/canning-101-sugars-role-in-home-preserved-food/