Blueberry Jam


So I’m not an expert canner. In fact, it’s a relatively new hobby. It’s something that my mom used to do a lot of when she was raising her kids and something she always intended to teach me how to do. Our first batch together was last year’s strawberry jam, in which we picked three times as many strawberries as we needed and ended up canning over sixty jars of jam in a day. I was fairly certain after that day that I never wanted to see a mason jar ever again but really all I needed was a little distance from Strawberrygate.


In the fall we tried orange marmalade and we managed to accomplish the task relatively unscathed. I was certain we had hit our stride, and that the strawberry catastrophe was a fluke. I had the utmost confidence in this year’s goal of blueberry jam (which also happens to be my favorite kind). Everything was wonderful and we spent hours strolling through miles and miles of rows of blueberries bushes. As we were departing from the most peaceful afternoon ever, fifteen pounds of blueberries in tow, we realized we had dropped the keys to the car somewhere on the farm. I’ll spare the gory details but there may have been mild swearing followed by hot crying. I’m still keyless.


Once I had regained (some) of my composure, we did manage to have a productive afternoon of canning that yielded just the right amount of jam. I’ve been thoroughly enjoying my daily breakfast of a buttered english muffin slathered in blueberry jam, so much so that I might almost concede it was worth losing my keys over. Almost.

Ingredients: sugar, pectin, fresh blueberries
Canning Supplies (from left-ish to right-ish): jar grabber, magnetic lid lifter, funnel, jars, lids, and rims, rim tightener (optional), clean towels, water bath canner.

What I’m learning about canning is that it can be a fickle and fussy business (and I’m not including my terrible luck in the equation). It requires a lot of mental sharpness and focus. (Basically, don’t drink and can.) You have to multitask like crazy, because everything needs to be hot at the same time so I would absolutely recommend starting with an impeccably clean kitchen and organizing your ingredients before your start. It also helps to have another person assisting in the process. And a fan. Or ten.


Difficulty aside, canning can be an incredibly rewarding and satisfying process. Knowing how to can makes me feel more in touch with history, when the ritual of food preservation wasn’t just a fun way to spend a weekend but a matter of survival. I look forward to popping open a jar mid-January, when everything outside is cold and dormant, and tasting luscious summer blueberries all over again.


Blueberry Jam

  • Servings: 5 half-pint (8 oz.) jam jars
  • Difficulty: intermediate
  • Print


  • 5 half-pint jars (I used Mason) + lids and rims
  • water bath canner + rack
  • jar lifter
  • kitchen funnel
  • wooden spoon
  • ladle
  • clean kitchen towels
  • magnetic lid lifter
  • jar tightener (optional)
  • timer

*I have this Granite Ware Canning Set, it has basically everything you need.


  • 7 cups fresh blueberries
  • 4 cups sugar
  • 1/2 teaspoon butter
  • 1 package (1.75 oz) Sure Jell Premium Fruit Pectin “For Use In Less or No Sugar Recipes” (the pink box)


1 Wash jars, lids, and rims in hot soapy water in clean sink. Rinse with hot water and set jars on a clean kitchen towel. Place lids and rims in a small pot on stove and bring to a boil. Once boiling, reduce heat to low and leave until ready to use.

2 Place the wire rack in the bottom of the canner and fill with enough water to cover the jars by 1-2 inches. (You may need to add water as it evaporates so just keep an eye on the water level and add more if needed).

Wash and pick stems off of fresh blueberries. Drain well and lay on a large baking sheet with a lip. Measure out exactly 7 cups of blueberries. Use a potato masher to crush berries until they are about 75% mashed. Measure out exactly 4 cups of smashed berries and place into a medium-large pot on stove. (At this point you will have three burners in use: a small burner for the lids and rims, a large burner for the water bath canner, and a medium/large burner for cooking the berries).

Place the washed jars into the canning pot and bring to a boil. Once the water boils, set a timer for ten minutes. After this time they are sterilized and ready to fill.

5 Meanwhile, add 1 package Sure Jell, and 1/2 teaspoon of butter to the mashed blueberries. Combine with a wooden spoon and turn on burner. Bring mixture to a roiling boil, stirring near constantly. When the mixture reaches a boil, add 4 cups of sugar and stir well. Wait for the mixture to return to a full boil. Once it does, cook exactly 1 minute and then turn off burner.

By now the jars should be completely sanitized. Use the jar grabber to lift hot jars out of the water, one at a time. Remove one jar, place funnel on the top, and use a ladle to fill with the jam mixture until it is 1/4 inch from top of jar. Dip a clean cloth in the hot water and gently wipe the rim and threads of the jar to remove any jam and ensure a clean seal. Using the magnetic lifter, grab a lid from the lid/rim pot and place directly on top of jar. Do the same with a rim. Tighten rim on jar and set completed jar aside (be careful not to tilt the jars to much, try to move them only directly up and down). Repeat steps until all 5 jars are filled and fitted with rims and lids.

Carefully place filled and capped jars upright on the rack and very gently lower down into the water (remember check the water level, there should be at least 1-2 inches of water above the tops of the cans). Place lid on pot and bring to a gentle boil. Once the water is boiling, set a timer for 10 minutes*. When the timer goes off, gently remove jars from the canner and set on a towel to cool completely (and away from drafts).

8 You should hear a pinging noise when the cans seal. Sometimes this takes minutes and sometimes it takes hours, be patient. After 24 hours, run your finger gently across the tops of the cans. If any of the lids have a bubble in the center that springs up and down when you push it, then it has not sealed properly. You will want to store unsealed jars in the fridge and use within 3-4 weeks. Store sealed jars in a cool, dry, dark place and they will keep for a year.

* Processing times can vary with altitudes so if you live at a high altitude, you will need to adjust (there are lots of good charts online for this).

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