Interested in learning how to can blackberry jam? Good! This was the first thing I learned to can and I have canned many a jar of jam since. I’m happy to share the step by step process of how to can blackberry jam with you.
This is one of the frugal things I am learning to do – can my own food. Growing up, I remember my Mom canning and my Grandma’s did as well.
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I was a bit nervous about the canning process at first but it really is very simple to do! I think canning jam is the perfect first canning recipe because anyone can do it.
The important thing to remember in any canning recipe is not to tweak the measurements, for food safety reasons. Always use a tried and true canning recipe like this one from the Ball book of canning.
Canning jam doesn’t require fancy equipment. You can actually make freezer jam that is also delicious. I prefer canning my jam so I can store it in the pantry without taking up freezer space. To do so, you need a water bath canner. A water bath canner is simply a large pot in which you can cover your canning jars with boiling water. Water bath canners are reasonably priced and a good investment if you plan to can regularly (and by regularly, even a couple times a year makes it a good investment in my book).
Ready to can some homemade jam?
Here’s how to can blackberry jam.
Start by preparing your canning jars.
Gather all your Ball canning jars and wash them in hot water. You can also sterilize them by washing them in your dishwasher if you plan on making several batches of jam in one day.
Canning jars come in many sizes. Half pint jars are the perfect size for jam. I use pint jars for salsa and quart jars for applesauce. You can decide on the size of jars that you would like to use. Half pint or smaller are really the best size for jam. These are the jars I use when canning jam although I know some prefer these 4 ounce size jars for jam, especially if you plan to gift some of it.
Now, you need to fill your clean jars with hot water to stay warm. This is very important because your jam will be warm when you fill your jars. If you put warm jam in a cold jar and submerge it in hot water, your jar will not seal properly and could very well crack.
You could fill them with boiling water from a teapot on the stove. I improvise. I turn my tap water as hot as it can go. It is almost boiling at this point. Then, I fill my jars with this scalding water and place the jars carefully on the counter to stay warm while I make the jam.
Finally, fill your water bath canner with hot water. Cover and bring to a simmer. At this point, I make sure my jar rack is hooked on the sides of the water bath canner and waiting for me to set the jars on it. Your wire rack that comes with most canners will have obvious ridges where you can hook it on.
The final thing you need to do is boil your lids and jar bands. I pour some hot water in a large glass bowl and drop my lids and jar bands in there until I am ready to use them.
Now, it’s time to make your blackberry jam.
First, gather your blackberries. To make one batch of blackberry jam, you will need 5 cups of crushed berries. That is approximately 3 pounds of berries or 8 cups of blackberries, if you were wondering. We have a member at church with blackberry bushes so when she calls with extra berries that need to be picked, I hurry over there for free blackberries!
Once you have your blackberries, deal with them as soon as possible. Wash your berries gently under cool water. Then, smash your blackberries with a potato masher or a sturdy metal spoon. It won’t take long and it doesn’t have to be a perfect puree. Some blackberry chunks are actually good!
Carefully dump your smushed berries and juice into a large pan on the stove. Stir in 1 package (1.75 ounce) package of fruit pectin. This helps it maintain the sweet, fresh flavor of your fruit. Bring jam mixture to a full rolling boil that cannot be stirred down, over high heat, stirring constantly.
Next, stir in seven cups of sugar. Yes, seven is correct. I know it is a lot but your jam will be delicious! Remember, it is very important that you don’t mess with the proportions in any canning recipe, for food safety reasons. It is also recommended that you do not double canning recipes for the same reason. If you want to make two batches of jam, simply make one after another so nothing happens with your proportions. If you want to make low sugar jam, follow a recipe specifically for that and buy low-sugar pectin instead.
Return jam to a full roiling boil. Boil hard for 1 minute, stirring constantly. Remove jam from heat. Skim foam if necessary or desired.
Now it is time to can your blackberry jam.
The best thing I did this year was to purchase a canning funnel. It fits perfectly into all sizes of canning jars and makes filling my jars a breeze! Before I had this funnel, I spilled everywhere. Thanks to this handy canning funnel, my canning is much neater now. It’s a simple canning investment that is worth the money spent.
Dump the hot water out of your clean canning jars and put an empty jar on the counter. Place the canning funnel in the jar and fill it with hot blackberry jam. I like to use a ladle for this part.
Fill your jam carefully leaving 1/4 inch headway. Hint: This is marked by the top line where your lid screws on. I tend to leave closer to one inch, right where the curves begin.
Once the jar is filled, remove the funnel. Using a damp paper towel, wipe the inside and outside lip of your jar.
Remove a lid and ring from the hot water. If you have a magnetic lid wand, you won’t burn your fingers! This is another great canning invention. Place the lid on top of your jar and screw the canning ring.
Carefully place your jar into your hot water bath canner on the wire rack. Repeat the process until all your jars and / or your canner is filled.
If you are using a water bath canner, you will have a wire rack that you can lower your jars into the warm water. After you lower the wire rack to the bottom, add boiling water to your canner until there is 1 to 2 inches of water above the lids of the jars.
Cover the canner and return water to a boil. Boil for 10 minutes. Do not start counting your 10 minutes until the water is at a full and steady boil.
Turn off the burner heat. Remove water bath lid and allow jars to cool in the canner. After 5 minutes, carefully remove the jars and place on a towel to cool. With all the steam still there, I use my jar lifter tool so I don’t burn my fingers. You probably should buy a canning tools set like this one if you plan to can even a couple times a year. You will be glad you have these handy tools. You will probably hear a popping sound as the lids seal. That is normal and a good sign that you have canned correctly.
Leave your jars to cool for 12 to 24 hours. Do not disturb them. I know it’s hard to be patient, but you need to be! At the end of 24 hours, press down lightly in the center of each lid. If if does not give, your jar has sealed properly. At this point, tighten the bands on your jar and label your jam.
See how easy it is?
You now know how to can blackberry jam!
Enjoy opening a jar of this delicious, homemade, frugal goodness and savor the taste on warm bread. Bonus points if your bread is homemade!
Canning really is simple, frugal and fun. Have you canned anything recently?
For further instructions on canning, I highly recommend the Ball Blue Book Guide to Preserving. It is the ultimate how-to canning book with clear directions on how to can hundreds of different things like fruits, vegetables, jams, salsas and countless other things.