Place all the ingredients in a slow cooker and cook for 2-3 hours on low.
4 tablespoons lemon juice, 3 strips lemon peel, 1/2 cup water, 1/2 cup honey, 1/4 cup maple syrup, 1 inch piece of fresh ginger
Remove ginger and mash with a potato masher or puree with an immersion blender (depending on desired texture).
If mixture is too thin at this point, turn crockpot to high and prop lid halfway off so steam can escape. Continue to cook for another 1-2 hours until it reaches the desired consistency, stirring occasionally.
Once jam reaches desired texture, store it in a mason jar in the fridge for a couple of weeks, freeze it (mind your headspace), or use the instructions below to can it for the pantry.
PREPARE FOR CANNING
Wash the jars you'll use, making sure each is clean and free of nicks in the rim, which could impede sealing.
Wash the lids and rings in hot soapy water. (If you're using non-Ball brand lids, prepare as suggested by manufacturer.)
Place empty jars in a canning pot or large stock pot with enough water to cover by an inch or two, cover pot, and set on high heat when jam is near done.
CANNING THE JAM
Ladle hot jam into quarter-pint, half-pint, or pint sized jars, leaving 1/4" head space. A canning funnel makes this easy.
Wipe jar rims to remove any jam that may have spilled. A clean rim is essential to a good seal.
Set jar lids in place. Screw bands on finger tight.
Use a jar lifter to gently submerge jars into hot water in the canning pot. Water should cover the top of the jars by an inch. The water will cool somewhat in reaction to the addition of the jars. Return the water to a simmer and then set the timer.
Process for 10 minutes 0-1,000 feet altitude; add an additional minute for every additional 1,000 feet in elevation.
Remove jars from water using the jar lifter and transfer to a solid, towel-covered surface. Allow to cool for 24 hours.
Check seals. Lids should be solid and pulled down tight. (if they flex and pop, the jar didn’t seal; put unsealed jars in the refrigerator and use those first).
Remove rings and wash outsides of jars. Store in a cool, dry place.
Notes
Recipe yields 2 pint jars.
The potato masher will leave a chunkier jam while the immersion blender will create a smoother jam.
Recipe as made tests at a pH of 4.0, making it safe for water bath canning.
Boiling lids or heating above 180°F as once recommended can damage the sealing compound.