Prepare boiling water canner. Heat jars in simmering water until ready to use. Do not boil. Wash lids in warm soapy water and set aside with bands.
2. Step
Place crushed berries and lemon juice in a saucepan. Sprinkle pectin evenly over berries, and bring mixture to a full rolling boil that cannot be stirred down, over high heat, stirring constantly.
3. Step
Whisk in agave syrup. Return mixture to a full rolling boil. Boil hard for 1 minute, stirring constantly. Remove from heat. Skim foam if necessary.
4. Step
Ladle hot jam into a hot jar, leaving a ¼-inch headspace. Remove air bubbles. Wipe jar rim. Center lid on jar and apply band, adjust to fingertip tight. Place jar in boiling water canner. Repeat until all jars are filled.
5. Step
Process jars 10 minutes, adjusting for altitude. Turn off heat, remove lid, let jars stand 5 minutes. Remove jars and cool 12–24 hours. Check lids for seal. They should not flex when center is pressed.
