- 6 cups pureed watermelon
- 5 cups sugar (white or brown)
- 1/2 cup bottled or fresh lemon juice
- 1 packet powdered pectin
- Combine watermelon puree, sugar and lemon juice in a large, non-reactive pot (anything but aluminum). Get one bigger than you think, you’ll want plenty of space for things to foam up without overflowing. Bring to a boil and let it boil vigorously until the temperature of mixture reaches 220 degrees. Be sure to stir frequently, you don’t want it to burn on the bottom. Add the powdered pectin and boil for another five minutes.
- Remove from the heat and pour into clean, sterilized jars, leaving about a half inch of head space. Wipe rims, apply lids and screw on bands. Process in a boiling water bath for 10 minutes.
- When time is up, remove from canner and let jars cool completely, preferably overnight. When they are cool enough to handle, remove rings and test seals. You can eat immediately or store unopened jars in a cool, dark place for up to a year.