Combine fruit, sugar, and lemon juice in large bowl. Let stand at room temperature 2 hours, stirring
occasionally. Put 2 saucers in freezer.
In bottom of heavy large stockpot at least 3 inches deeper than height of jars, place metal rack or
extra screw bands from canning jars to protect jars from direct heat. Fill pot with water, cover, and
bring water to boil. Reduce heat to low. Wash jars, lids, and screw bands in hot soapy water; rinse
well. Set screw bands on clean towel to dry. Place lids in small saucepan; cover with cold water and
bring to simmer; turn off heat. Fill jars with very hot water.
Transfer fruit mixture to large saucepan and bring to boil over medium-high heat, stirring
occasionally. Mash to thick puree with potato masher. Reduce heat to medium and boil gently until
mixture begins to thicken, stirring often, about 18 minutes.
Remove saucepan from heat to test jam for gelling point. Drop 1 teaspoonful jam on chilled saucer
and return to freezer 1 minute. Remove saucer and push edge of jam with fingertip. If jam has
properly gelled, surface will gently wrinkle. If not, return saucepan to heat and cook jam a few
minutes longer; repeat test.
Drain hot water from jars and shake out excess water. Place jars on cutting board. Ladle hot jam into
each jar, leaving 3/4-inch space at top. Slide flat plastic spatula between jam and jar to eliminate air
bubbles. Clean rim of each jar with damp cloth. Using tongs, lift hot lids from saucepan, 1 at a time, shake dry, and place atop jars. Seal each with screw band, twisting to close but not too tightly. Return filled jars to pot of hot water. Add water to pot, if necessary, to cover jars by at least 1 inch. Cover pot and bring to boil; reduce heat
and boil gently 10 minutes. Turn off heat. Wait 5 minutes; use tongs to remove jars without tilting.
Place upright on towel; cool completely at room temperature. Jam will thicken as it cools.
Check lids for seal by pressing each lightly. Lids of sealed jars will be concave and show no
movement when pressed.
Sealed jars may be stored in a cool, dry, dark place for up to one year. Unsealed jars must be
refrigerated and jam must be used within a few weeks. For an even quicker jam, skip the canning
instructions, ladle hot jam into clean jars, and store the jam in the refrigerator for up to two weeks.
For peach or apricot jam, use 2 pounds fruit, 2 cups sugar, and 2 tablespoons lemon juice. Rinse, dry, and rub any fuzz off peaches, if using. Halve, pit, and cut fruit into 3/4-inch pieces. Place in bowl and toss with sugar and lemon juice, then follow directions above.