· Wash the wild plums
· Place the plums in a large stockpot or pressure cooker, and add water until it's just below the top of the fruit in the pots.
· Place the stockpot over medium-high and bring the water and plums to a boil. Reduce the heat to medium-low, and then covered for about 10 minutes, or until the fruit is soft.
· Use a potato masher as the fruit is simmering to break the skins and separate the flesh from the pit.
· Use a colander first to drain the liquid let sit in colander for at least an hour and smash out any liquid that forms on top.
· After colander use a jelly bag or cheesecloth and place over a large bowl. Pour the cooked wild plum juice into the jelly bag or cheesecloth, and then allow them to sit until filtered.
· Measure the juice in the bowl, and then transfer it to a saucepan.
· Bring the plum juice to a boil over medium-high heat, and continue for 3 to 4 minutes.
· Add 3/4 cup granulated sugar for each cup of juice in the pan.
· Add the zest of one Myer Lemon.
· Stir to combine and bring to a boil.
· Continue boiling, uncovered, until the mixture begins to turn to jelly, usually about 20 minutes.
· Check the wild plum jelly for doneness by placing a cold spoon into the mixture. Lift it out, and if the liquid coats the back of the spoon, it's reached the jelly stage. If not, boil for an additional 1 to 2 minutes and check again.
· Transfer the wild plum jelly into the sterilized canning jars, leaving about 1/4 inch of space at the top.
· Secure the lids in place and process the jars for 10 minutes in a boiling water bath.