In food processor or blender, process rose petals, lemon juice and 3/4 cup water. Slowly add sugar until thoroughly blended. Pour mixture into large bowl (a large mixing bowl with pouring spout is ideal). Set aside. Combine pectin and 3/4 cup water in small saucepan. Stir to dissolve and bring to a boil. Allow pectin to boil hard for one minute. Pour pectin over the rose petal mixture and stir. This will start to set very quickly. Spoon or pour mixture into clean containers and refrigerate. It will continue to set as it cools.