• Equal measurements of clean, washed Blackberries and sugar – (example 6 cups blackberries and 6 cups sugar)
• Juice of 2 fresh lemons
• Mason jars and lids
Wash Blackberries and remove any remaining stems. If using Blackberries from your home garden, make sure to add a few red berries (unripe ones). The red berries are not sweet, but they do contain an added amount of natural pectin.
Place berries into a large pot and add sugar. Mix and allow to stand for 15 to 20 minutes so the berries and sugar can start to breakdown. Add juice of 2 lemons and heat mixture to boiling. Turn heat down so mixture is just under a rolling boil and cook for 20 to 25 minutes. Skim foam off the top as needed (this recipe produces less foam than when using pectin). Some people find it easier to use a jelly thermometer to get the correct temperature, but I again use a technique from my Granny. I keep a small saucer in the freezer and when I think the jam is ready, I remove from freezer and drop a small amount of jam onto the frozen saucer. If the jam immediately jells, it is ready. If it remains runny, keep cooking for a few more minutes.
When the jam is ready, ladle into clean sterilized jars and apply hot lids and screw-down caps. Immediately turn the jars upside down and keep this way for 20 minutes. Then turn jars right side up. You should hear the tell-tell sound of the lid “popping” as the jar seals. Jam can be stored for one year in a pantry. Refrigerate jars after opening; then use within one month.