How to Make Blackberry Jam: Blackberry Jam Recipe

Here we are in late summer, time to harvest luscious fruits. Hailey and I sampled melons and picked raspberries, strawberries and even figs at our CSA farm this week.

How very sweet!

One of our main activities this time of year is preserving the fruits of summer.

We canned peaches this week. I’ve made strawberry and rowan berry jam, and this week my friend Jen and I made blackberry jam sweetened with honey using my favorite blackberry jam recipe.

Since jam making is one of the most delicious ways to preserve the goodness of the plants, we thought we’d share how to make blackberry jam with this simple blackberry jam recipe (adapted from the book Stocking Up III).

For your blackberry jam recipe, you will need…

  • About 5 cups of mashed up blackberries
  • A box of pectin which indicates it’s for no or low sugar recipes (available at any super market this time of year)
  • 6 tsp. of lemon juice
  • 2/3 of a cup of honey for the blackberry jam recipe

This will make about 6 cups of finished blackberry jam.

First sterilize your jars by boiling them for 10 minutes or more. Drop the lids in the water after you’ve removed it from the heat and allow them to sit in the hot water until you’re ready for them.

Mix the pectin into the honey.

Next put the mashed berries and lemon juice into a large pot and bring the mixture to a boil – stirring often.

Stir in the pectin-honey mixture and return to a boil – stirring constantly.

Check to see if the jam is set by putting a spoonful into the freezer for a few minutes.

If it is jelled when you take the spoon out, the blackberry jam is ready. (If it is not jelled simmer a few more minutes while continuing to stir and repeat the test.)

Remove the jam from the heat and pour into your sterilized jars. We use a Pyrex measuring cup, are great for pouring the blackberry jam into your jars. Wipe the rims of the jars.

Put the lids on and process in a canner to seal the jars. What you see here is a steam canner (without the top lid). For jams, steam canners are fast and simple. Follow the directions on your canner on how to use it as well as how many minutes to process for.

You can also use the boiling water bath method. To do this, submerge jars in water (they shold sit on a canning rack) leaving 1 to 2 inches of water covering jars. Leave enough room in between jars for water to circulate. When it comes to a rolling boil, let it do so for 20 minutes. Water should be covering the jars the entire time.

With whichever process you use, remove jars when finished and let cool on a towel. Do not turn jars upside down.

Check for sealing before storing. If one or two did not seal, just put those in the fridge and use first. You could also try re-canning.

3-Way Test For Checking The Seals On The Jars:

  • Hear the seal – Hear the “plink” as lid snaps down while jar is cooling, or tap lid with spoon when jar is cold. A clear ringing sound means a seal.
  • Observe the seal – If the lid is curved down, the jar is sealed.
  • Press the seal – After the jars have cooled, press the center of the lid. If it is down and will not move, the jar is sealed.

Remove ring bands from jar and store in a cool, dark, dry place. Ring bands free of rust may be reused. Never reuse lids for canning purposes.

CAUTION: Never taste or eat food from a jar with an unsealed lid, swollen lid, or if the food shows signs of spoilage.

That’s it! Now you know how to make blackberry jam.

Now you can enjoy your wonderful summer treat throughout the year, or give the blackberry jam recipe as holiday gifts. Blackberry is my sister’s particular favorite so I make a batch for her each summer.

Enjoy our blackberry jam recipe!