125g/4Β½oz fresh root ginger (100g/3Β½oz prepared weight), peeled and cut into 5mm/β…•in cubes or grated
1.2kg/2lb 10oz rhubarb (1kg/2lb 4oz trimmed weight), trimmed and sliced diagonally into 2–3cm/1in slices
pinch sea salt
700g/1lb 9oz jam sugar
100ml/3Β½fl oz freshly squeezed orange juice