- In a large heavy saucepan, combine blueberries, rhubarb, lemon rind and
- juice and water. Bring to a boil, stirring frequently, reduce heat and
- simmer, very gently, for 10 minutes.
- Stir in sugar; increase heat to high and boil vigorously until jam reaches setting point. (218 - 220 degrees F), 10 to 15 minutes, stirring
- Remove from heat, skim off foam and stir for 3 to 5 minutes to suspend
- fruit evenly throughout jam.
- Fill prepared jars leaving a 1/4" headspace. Process in a boiling water bath for 10 minutes. Adjust time according to your altitude.