Wash lemon and strawberries under cold running water; drain. Cut off yellow layer of lemon peel. Thinly slice lemon peel; measure 1/4 cup sliced lemon peel. Remove stems and caps from strawberries. Crush strawberries one layer at a time using a potato masher. Measure 4 cups of crushed strawberries.

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.

Combine lemon peel and water to cover in a 6- or 8-quart saucepan. Bring to a boil over medium-high heat and boil for 5 minutes, until peel is softened. Drain and discard liquid. Return peel to pan.

Add strawberries and bottled lemon juice to peel and mix well. Gradually stir in pectin. Bring mixture to a full rolling that cannot be stirred down, over high heat, stirring constantly.

Add entire measure of sugar, stirring to dissolve. Return mixture to a full rolling boil. Boil hard for 1 minute, stirring constantly. Remove from heat. Skim off foam if necessary.

Ladle hot jam into a hot jar leaving a 1/4 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.

Water must cover jars by 1 inch. Adjust heat to medium-high, cover canner, and bring water to a rolling boil. Process half-pint jars 10 minutes, adjusting for altitude. Turn off heat and remove cover. Let jars cool 5 minutes. Remove jars from canner; do not retighten bands if loose. Cool 12-24 hours. Check lids for seal, they should not flex when center is pressed.