Wash the hips well and put into a preserving pan with water. Simmer for 2 hours. Put into a jelly bag and leave to strain overnight. Peel, core and slice the apples, add to juice and cook until pulped. Stir in the sugar and cook over a low heat until dissolved. Bring to the boil and boil rapidly until setting point is reached. Pour into hot sterilized jars and cover tightly.