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Blackberry jam is one of my absolute favorites. I had never even tasted blackberries, or their delicious jam, until I was probably a teenager sitting at a cracker barrel one day. And it was then that I became hooked to its deliciousness.
Blackberries are a delicious summertime fruit. We have a few wild patches of blackberries around here, but I can’t wait until we add a few bushes to our homestead next spring. I can make all the jam I want in a couple of years after that….
While making jam is something I’m not particularly good at, I do keep trying. And with every try, I get better and better. I am not good at any jam that uses pectin. Like my strawberry jam recipe . I just can’t ever quite get it just right. It’s either overcooked or undercooked every time. And while I can fix it, and I always do, I just haven’t quite perfected the art of jam making.
Thankfully, blackberries are naturally high in pectin so I don’t have to worry about adding any. Which makes this jam, and my raspberry jam, super simple and easy to make. This blackberry jam only takes 3 ingredients and about 20-30 minutes to cook. Did I get it perfect? No… I ended up having to add a little port to it to thin it back down. But, it’s delicious, even when it was too thick.
And next time? I’ll do better. Everything takes practice and we all have to start somewhere. The first time I made jam I made a massive sticky mess. This time? Clean up was a breeze.
And, the farm girls helped me accomplish it as part of their homeschool lessons for the day. They kept it stirred to keep the foam down (blackberry jam foams quite a bit and needs watched). They helped ladle it into the hot jars and learned a little bit about canning safely. And we got to spend some quality time together making not only food, but memories.
While typical jam calls for equal amounts of sugar and fruit, like in my raspberry jam recipe, I wanted to make this a little less sweet. So, we didn’t add anywhere near equal amounts of sugar to this batch and it still turned out absolutely delicious. How much sugar you do add, however, is entirely up to you. The blackberries can actually be safely canned without any sugar at all and they have all the pectin they need naturally, so this recipe is really pretty straightforward.
Tips for Making Blackberry Jam
- The more sugar you use, the less your jam will need to reduce before it gels. Which means, you’ll yield more jars the more sugar you use and spend less time cooking it down.
- Every batch is going to be slightly different, so you’ll need to check for gelling. The simplest way to do this is to place a clean, dry, cool spoon into your syrup. Pull it out and when the jam starts dripping off in sheets (two drops at a time forming a sort of “sheet”) it is gelled and ready for canning.
- You can substitute honey for the sugar in this recipe. I tested it and it cooked down, but took a while longer. Others say you need to add another high-pectin fruit (grated apple or a cup of cranberries). The thing with honey is it adds liquid to your recipe. If you use honey, I would use less as it is sweeter. It may take slightly longer to cook down.
- Blackberry jam has a tendency to foam quite a bit while cooking. It’s important that you watch the pot continuously and stir frequently to keep the foam stirred down.
- You can add a 1/2 tablespoon of butter to any jam recipe to reduce foaming, but it creates an off-taste to some people once it’s canned and has sit.
- If the blackberry jam hasn’t gelled, it needs to cook longer.
- Reduce the heat to low as it gets closer and closer to gelling to avoid scorching it (which is no fun to clean up and doesn’t taste good, ask me how I know….)
- This recipe can be multiplied up to 3 times to yield roughly 12 half pint jars. Do not increase it beyond that as batches larger than this have trouble reaching gel stage.
- You can make this jam seedless by putting the berries through a food mill or fine mesh sieve before adding the berries to the pan.
- Overcooked jam can be fixed before it is canned (as long as it isn’t scorched) by adding a bit of boiling port (which is delicious) or boiling fruit juice to the jam little bits at a time until it is the right consistency.
- Undercooked jam can be fixed by combining the canned jam with 2 teaspoons of sugar, 2 teaspoons of juice or port wine, 1/2 Tablespoon of lemon juice and 1 teaspoon of powdered pectin per half pint of jam and bringing it to a hard boil and allowing it to hard boil for 1 minute. Then, remove it from the heat, test for the gel stage and jar it up and process it like you did before.
- 6 Cups Blackberries (fresh is best, frozen can be completely thawed first)
- 3 Cups Pure Cane Sugar (more or less to taste)
- 3 Tablespoons Lemon Juice
- Begin by placing all of your ingredients into a wide, shallow saucepan. The wider pan will allow your jam to cook more evenly. If you want seedless jam, simple run your blackberries through a food mill or fine mesh sieve before you place them into the pan.
- Place the pan over medium-low heat and start to stir to mix the ingredients together until the sugar has dissolved making sure to keep the sides of the pan scraped.
- While the mixture is cooking, mash up your fruit with a potato masher if you didn't make it seedless before starting.
- Bring fruit mixture to a boil over medium low-heat taking care to keep the foam stirred down. Cook at a boil until the mixture begins to gel. You'll know it's ready when it comes off of a clean spoon in a sheet.
- Carefully ladle hot jam into sterilized jars, leaving 1/4" of headspace.
- Wipe rim and center lid on jar. Finger tighten ring. Place jars back into canner.
- Put the lid on canner and process jars for 10 minutes.
This recipe can be canned without any additional ingredients beyond the blackberries and still be canned safely, so feel free to adjust the sugar amounts and lemon juice to your liking either by omitting or increasing them. The more sugar you use, the quicker it will gel and the more yield you will receive. Less sugar will result in a smaller yield.
If you do not want to process this to make it shelf stable you can cool it and place it in the fridge where it will keep for up to 3 weeks.
Other Jam Recipes You’ll Love:
Do you make your own homemade jam? What’s your favorite?