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Strawberry Jam
Total 2 hours (plus cooling time)
Active 45 mins
Makes 8 to 10 (8-ounce) jars of jam
My mom always made jams when I was growing up, and as a kid, I considered helping with jam-making a chore. But when I grew up, I realized how much more flavor homemade jam has, and once I started making my own, I never wanted to go back to store-bought. I make jam in big batches, but the general proportions—half sugar, half fruit—work for any size batch you want to make. It’s worth noting that while this recipe feels like it uses a ton of sugar (and it does), the sugar is what preserves the fruit and keeps it from developing bacteria. Use lemon juice—lemon skin and seeds contain natural pectin -- and the juice activates the pectin from the strawberries too.
TIP: Before opening and eating, carefully examine all home-canned jars of food for signs of spoilage. If there is any mold in a jar of jam, or signs of other spoilage, toss the entire contents of the jar or container without tasting it. Use a flat wooden spatula to stir the jam so that you can effectively scrape the bottom of the pot and keep the sugar from burning. If you don’t want to can your jam in a water bath canner, you can simply make a small batch and refrigerate the rest.
Special Equipment
a canning pot; ten 8-ounce canning jars with band and fresh lids; canning tongs (for removing jars from the pot)
Special Equipment
a canning pot; ten 8-ounce canning jars with band and fresh lids; canning tongs (for removing jars from the pot)
    • 11 heaping cups strawberries, cored and halved
    • 11 cups granulated sugar
    • 3 lemons, juiced (about 1/2 cup), seeds removed, and halves reserved
  1. Put the strawberries and sugar in a large pot over medium heat and cook, mixing constantly and scraping the bottom of the pot, until the strawberries begin to release their juices and the mixture becomes a little bit soupy, about 5 minutes.
  2. Add the lemon juice, turn the heat to medium-high, and use a potato masher to crush the strawberries. Put the reserved lemon halves into the mixture to release their pectin, and let the jam simmer, skimming the foam off of the top of the pot until the sugar is dissolved, 10 to 15 minutes. Lower the heat and simmer, stirring frequently and scraping the bottom and sides of the pot, until the jam is thick and slides off the spoon in a sheet instead of dripping, about 1 hour. (Alternatively, test the jam by putting a plate in the freezer before you begin; then drop a small dollop of jam on the frozen plate and run your finger through it—if the jam holds and doesn't run back together, it is done.)
  3. Remove the lemon halves.
  4. Prepare the water bath for canning: Wash ten 8-ounce canning jars with bands and fresh lids in soapy water, rinse well, and set aside to dry. Fill a canning pot about halfway with water. Fill your jars with hot water and submerge them in the pot (you’ll need enough water to cover the jars by a couple of inches once submerged). Bring the water to a boil and boil the jars for 15 minutes to sterilize them.
  5. Working with one jar at a time, remove the jar from the pot with canning tongs, draining out the water, and set it on the kitchen counter. Using a scoop or a ladle and a funnel, fill each jar to 1/4 inch below the top with the warm jam (it shouldn’t be filled all the way to the top, or you won’t achieve a proper vacuum seal). Top the jar with a lid, screw the band on finger-tip tight (not tighter, because air needs to be able to escape), and return the jar to the pot. The yield will depend on how juicy your strawberries are, so you might end up filling fewer than 10 canning jars.
  6. Process the jars according to the instructions on the packaging for your lids (generally about 15 minutes). Remove the jars from the water, set them on a heat-proof counter or a kitchen towel, and let them cool undisturbed for 12 to 24 hours. Do not tighten ring bands on the lids or push down on the center of the flat metal lids until the jars are completely cooled. The lids will make a popping sound as the air in the jars contracts, sealing the lids. When the jars are cool, check the seals by pressing on the lids; they should be flat and slightly indented, without a dome on top, and should not move when you press them. Keep the jars in a cool, dry, dark place (between 50 and 70 degrees F) for up to 1 year. (See Cook's Note.)