Home Canning: How to Can Your Own Strawberry and Blueberry Jam

Making homemade strawberry and blueberry jam is a wonderful way to capture the flavor of summer to enjoy year-round. Here’s how to can your own strawberry and blueberry jam.

Pick Your Berries

The only rule here is to avoid any soft or mushy berries.

You will need about 6 cups (or 2-1/4 pounds, or 3 dry pints) of blueberries for each batch of blueberry jam and 4 dry quarts (or 8 dry pints, or 6 pounds) of strawberries for each batch of strawberry jam.

Increasing the size of the batch of jam (i.e., by doubling or more) is not recommended, as this will prevent the jam from setting properly. Of course, you can make as many small batches of jam as you’d like.

Prepare Your Canning Equipment

Sanitize about seven or eight half-pint canning jars and lids. To sanitize, place the jars in the dishwasher and run it on the hottest cycle. Keep the jars warm by using the dishwasher’s “heated dry cycle” until the jam is ready to be jarred. For sanitizing without a dishwasher, wash the jars in hot water and rinse them well. Next boil them in the canner for 10 minutes and keep them in the hot water until the jam is ready to be jarred. To sanitize the lids and screw bands, fill a saucepan about 2/3 with water and bring it to a simmer. Place the rings and lids in the hot water and allow them to simmer for 5 minutes. Use tongs and magnetic lid lifter to remove the screw bands and lids. Put them on a clean kitchen towel until you are ready to use them.

Now it’s time to make some jam!

Strawberry Jam

  • 4 dry quarts of strawberries
  • 6 cups sugar

Wash, hull, and crush the strawberries (use a potato masher, food mill, or food processor on the “pulse” cycle for this).

Combine crushed strawberries and sugar in the pot. Heat the mixture slowly, bringing it to a boil. Stir frequently to avoid scorching. Continue cooking and stirring until the jam reaches 221°F and thickens to the desired consistency. This may take as long as 45 minutes.

Remove the jam from the heat and skim the foam from the top. Stir the jam for another 5 minutes as it cools (this prevents the fruit from floating to the top).

Follow the directions for processing the jam jars below.

Blueberry Jam

  • 6 cups blueberries
  • 5 cups sugar
  • ¼ cup lemon juice

Wash the berries, removing any stems or leaves. Crush the blueberries (use a potato masher, food mill, or food processor on the “pulse” cycle for this).

Combine crushed blueberries, sugar, and lemon juice in the pot. Heat the mixture slowly, bringing it to a boil.

Stir frequently to avoid scorching. Continue cooking and stirring until the jam reaches 221°F and thickens to the desired consistency (about 30 minutes).

Remove the jam from the heat. Skim the foam from the top. Stir the jam for another 5 minutes as it cools (this prevents the fruit from floating to the top).

Follow the directions for processing the jam jars below.

Filling and Processing the Canning Jars

Fill the half-pint canning jars with jam, leaving a quarter-inch of space at the top. Wipe away any dripped jam from the rim of the jar. Put the lid on the jar and screw the band on tightly. Load the jars into the canner full of boiling water. Process the jars for five minutes (canning at more than one thousand feet about sea level will require an increase in processing time).

Remove the jars from the boiling water after 5 minutes. Place them in an area free from drafts to cool (leaving them overnight is best). After cooling, verify that the jars have sealed properly by pressing the “button” of the lid. If the center of the lid pops up and down, the jar has not sealed properly. The jam can still be eaten if it is refrigerated immediately.