Watermelon Preservers Pare and cut in stripes the rind of ripe watermelon. Soak in salt water over night. Cook in fresh water the next morning until tender. Drain. Add equal weight of sugar and let stand again over night. Add one-half as much of water as sugar and cook until clear. For flavoring, add while cooking one sliced lemon and a few pieces of ginger root, or a stick cinnamon and white cloves. If a sweet pickle is desired, add one cup vinegar to a melon.