Begin by washing about four cups of fresh mulberries under cool water. Gently drain them, then add them to a wide, heavy-bottomed pot. Crush roughly one-third of the berries to release their juices.

Add 1/4 cup of freshly squeezed lemon juice and the finely grated zest of one lemon. Stir in 1 1/2 cups of granulated cane sugar, a pinch of salt, and 1 package of low-methoxyl pectin. Stir well until all ingredients are combined.

Place the pot on the stove over medium-high heat. Stir continuously, ensuring that the sugar dissolves completely. The texture should become slightly thicker and glossy after about 3–5 minutes.

Raise the heat to bring it to a rapid rolling boil. Allow it to cook for 5-7 minutes, stirring occasionally to prevent sticking. The jam should bubble vigorously.

Use a digital thermometer to check the temperature; aim for 220°F (104°C) for proper gelling. If you don’t have a thermometer, perform the plate test by spooning a small amount onto a chilled plate.

Remove the pot from heat and let the jam sit for about 2 minutes. Carefully ladle the hot jam into sterilized jars, leaving a little space at the top. Seal the lids tightly and let them cool to room temperature.