Olallieberry (Blackberry) Freezer Jam

fresh OlallieberriesHooray for summer and all the tasty fresh fruits that come along with it! The season for Olallieberries here in California is June and it usually only lasts a few weeks. If you are not familiar with Olallieberries they are a cross between two blackberry hybrids.

We like to go to a local farm and pick our own berries. It’s a fun day out with the kids and I can get beautiful fresh berries for around $2 a pound.

Picking olallieberries

Picking olallieberries has become a traditional summer kick-off activity.

So what am I making with the 10 pounds of tart-sweet berries we picked?¬† This year I’m making freezer jam.

If you are a little intimidated by making jam,  freezer jam is a great way to start. It is much faster and easier than canning. No special equipment is required. You just need instant pectin, plastic or glass jars and freezer space to store your finished jam. And the best part is freezer jam tastes more like fresh fruit than cooked jam!

For 6 half pint jars (=3 pints)


2 cups white sugar
6 TBSP instant pectin
5 cups mashed olallieberries or blackberries (8-10 cups whole berries)


  1. In a large bowl mix together the sugar and pectin. Set aside.
  2. Place berries in a colander and rinse with cold water. Allow to drain then gently spread out on paper towels or a clean kitchen towel to allow any remaining water to drain.
  3. Place 1/3 of the berries in a bowl and begin smashing with a potato masher or similar tool. When they are mostly broken down add more berries and continue mashing until you have 5 cups of mashed fruit.
  4. Pour mashed berries into the bowl with sugar and pectin. Stir for 3 minutes.
  5. Ladle jam into freezer-safe containers, leaving 1/4″ space at the top. Let stand 30 minutes.
  6. Place in freezer. Take jam out as needed and place in refrigerator to defrost. Jam can be stored frozen up to a year.


  • I made strawberry freezer jam last summer and it was great. The same process can be used with fresh blueberries, raspberries or cherries.
  • Peaches require the addition of lemon juice and slightly different method, see the pectin jar label for details.
  • Do not double this recipe. Six half pints (3 pints) is the maximum recommended batch size when using instant pectin. Any more and your jam may not thicken properly.
  • You can freeze in glass canning jars or in plastic containers. Most new glass canning jars are freezer-safe, but check the label on the box to be sure. (The glass jars are not sealed.) When I made the second batch I used pint size plastic Ziploc Twist N Loc containers with a screw on lid.
  • Ball sells special plastic freezer jam jars, but any small clean freezer-safe container with straight sides will work.