Interested in canning blackberry jam? It’s very simple! Follow these step by step directions for how to can blackberry jam.
8 cups blackberries, smushed
7 cups sugar
1.75 ounces of fruit pectin
Water bath canner
Start by preparing your canning jars. Gather all your Ball canning jars and wash them in hot water. Fill your clean jars with hot water to keep them warm as you make the jam.
Fill your water bath canner with hot water. Cover and bring to a simmer on the stove.
Boil your lids and bands, allowing them to sit in hot water as you make the jam.
Gather and gently wash 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.
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. Bring jam mixture to a full rolling boil that cannot be stirred down, over high heat, stirring constantly.
Stir in seven cups of sugar. Return jam to a full roiling boil. Boil hard for 1 minute, stirring constantly. Remove jam from heat. Skim foam if necessary or desired.
Pour 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.
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. 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.
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 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.
Leave your jars to cool for 12 to 24 hours. Do not disturb them. 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.