Seedless Blackberry Jam

When I was young my Dad would go out and pick blackberries on his overly cultivated canes out back. He put a lot of time into weeds….some guys went to the bar after work, my Dad spent his in the thorns. Which meant if my Dad got a huge mixing bowl full, my Mom would be making jam before bed that night. Apparently I’ve married a man who enjoys tending to blackberry canes and who picks them for me….and I stay up late canning a batch. However, I don’t like blackberry seeds. I never did, as a kid I hated them. Making it seedless however is easy if you have the right tools. A cheap food mill in the canning section will last for many years, and makes the job quick!


Seedless Blackberry Jam


  • 5 cups prepared berries (measured AFTER prepping, see below)
  • 7 cups granulated sugar
  • 1.75 ounce package pectin (such as Sure Jell)


Wash jars, with bands and new lids, in hot, soapy water. Rinse well, and drain on a clean kitchen towel. Add jars to the rack of a canning kettle, fill pot halfway, bring to a simmer. Bring a small saucepan of water to a boil, turn off heat, add in lids and rings, set aside.

Mash berries with a potato masher in a mixing bowl. In small batches, add a bit of the berries to a food mill, set over a large bowl. Run them through, scraping the bottom as needed, till you push out the majority of the liquid. Discard seeds, and continue till done. (Note: Don’t discard the seeds in your home compost if you have one, they will survive!) Let the liquid sit for 10 to 15 minutes to settle (it will have a thick foam on top), scrape it off and use the thick juice.

Following the directions with the pectin, measure and put berry mixture in a large pot, stir in pectin. Bring to full rolling boil over high heat (a boil that doesn’t stop when stirring). Stir in sugar quickly, return to a full rolling boil, cook for 1 minute after it returns to the boil. Take off the heat.

Drain jars using tongs, place on a clean kitchen towel (make sure canning pot is over high heat). Ladle the hot jam into the bars, using a sterilized canning funnel. Leave a ¼” headspace.

Dip a clean paper towel in hot water, then run around the top of each jar. Place a lid on each jar, then a band, screw on finger tight.

Place jars in water bath rack, lower rack into water. Water should cover by 1 – 2″. Bring to a rolling boil, covered, process for 10 minutes, once it starts boiling. Turn off the heat, carefully remove jars, placing on a clean dry kitchen towel to cool.

Once cooled, check again that seals are down (you should hear the Ping! as each one seals). Gently remove bands (wash, dry and store for your next project. While they look nicer on, if they have water inside from processing, they can rust. If you are giving away your canned items, you can always slip one back on), note on jar or lid what is in jar with a date. Store in a dry/cool/dark area and use within a year.

As always, if you ever go to use a canned item and the lid is not sealed anymore, or bulging, discard it immediately. (I have only ever lost one jar in all my canning, so don’t fret!) If you are using a different brand of pectin, be sure to read their directions and to follow them.

Makes 5 pint jars, although most any size mason jar can be used, with about 10 cups jam produced.