Cook the rosellas with a little water, until soft, and puree in a blender. Measure how many cups of pulp, and add to it half the measurement in sugar. Bring to the boil and simmer, until a tablespoon of the jam shows that it is setting, by thickening when it is placed on a cool saucer. This may take 15-30 minutes of simmering. When the jam shows it is setting, fill into jars and seal. Include some of the seeds (secured in a small bag or cloth) to provide natural pectin to assist. You can use 1 cup of honey to 4 cups of pulp as an alternative to sugar but the jam would then need to be kept in the fridge to prevent mould from growing.