Using a sharp pointed knife, cut oranges into halves horizontally. This should be done by inserting knife point in diagonally, zigzagging the cut. Each half would have a serrated edge to give a flower shape. Scoop out segments carefully, without injuring the shells. Scrape insides of shells lightly with a blunt knife if required. Extract juice from segments, strain and keep aside. Keep shells aside in a covered box in fridge till required. Put water to boil, 1 tbsp. sugar, stir in jelly crystals, dissolve. Take off fire, cool a little, add lemon juice,rind,orange juice, cool to room temperature. Put mixture into fridge, till thick but not set. Whip cream and sugar till soft peaks form. Put in icing bag with giant star nozzle, chill til required. Pour thickened mixture into orange shells, arrange sturdily in tray. Put in freezer till jelly sets firmly. Top jelly lilies with swirl of whipped cream before serving. Serve each lily as individual helping with an appropriate spoon to scoop jelly.